Threats to the Homeland

Radical Islamist terrorism in its many forms remains the most immediate global threat to the safety and security of U.S. citizens at home and abroad, and most of the actors posing such a threat originate in the greater Middle East. More broadly, threats to the U.S. homeland and to Americans abroad include terrorist threats from non-state actors such as al-Qaeda that use the ungoverned areas of the Middle East as bases from which to plan, train, equip, and launch attacks; terrorist threats from state-supported groups such as Hezbollah; and the developing ballistic missile threat from Iran.

Terrorism Originating from al-Qaeda, Its Affiliates, and the Islamic State (IS). Although al-Qaeda has been damaged by targeted strikes that have killed key leaders in Pakistan, including Osama bin Laden, the terrorist network has evolved in a decentralized fashion, and regional affiliates continue to pose potent threats to the U.S. homeland. The regional al-Qaeda groups share the same long-term goals as the parent organization, but some have developed different priorities related to their local conflict environments.

Al-Qaeda in the Arabian Peninsula (AQAP) has emerged as one of the leading terrorist threats to homeland security since the al-Qaeda high command was forced into hiding in Pakistan.

Yemen has long been a bastion of support for militant Islamism in general and al-Qaeda in particular. Many Yemenis who migrated to Saudi Arabia to find work during the 1970s oil boom were exposed to radicalization there. Yemenis made up a disproportionate number of the estimated 25,000 foreign Muslims who flocked to Afghanistan to join the war against the Soviet occupation in the 1980s. They also make up a large segment of al-Qaeda, which was founded by veterans of that war to expand the struggle into a global revolutionary campaign.

Al-Qaeda’s first terrorist attack against Americans occurred in Yemen in December 1992, when a bomb was detonated in a hotel used by U.S. military personnel involved in supporting the humanitarian food relief flights to Somalia. Al-Qaeda launched a much deadlier attack in Yemen in October 2000 when it attacked the USS Cole in the port of Aden with a boat filled with explosives, killing 17 American sailors.1

Yemen was a site for the radicalization of American Muslims such as John Walker Lindh, who traveled there to study Islam before being recruited to fight in Afghanistan. Seven Yemeni Americans from Lackawanna, New York, were recruited by al-Qaeda before 9/11. Six were convicted of supporting terrorism and sent to prison, and the seventh became a fugitive who later surfaced in Yemen.

Yemen has become increasingly important as a base of operations for al-Qaeda in recent years after crackdowns in other countries. In September 2008, al-Qaeda launched a complex attack on the U.S. embassy in Yemen that killed 19 people, including an American woman. Yemen’s importance to al-Qaeda increased further in January 2009 when al-Qaeda members who had been pushed out of Saudi Arabia merged with the Yemeni branch to form Al-Qaeda in the Arabian Peninsula.

AQAP’s Anwar al-Aulaqi, a charismatic American-born Yemeni cleric, reportedly incited several terrorist attacks on U.S. targets before being killed in a drone air strike in 2011. He inspired Major Nidal Hassan, who perpetrated the 2009 Fort Hood shootings that killed 13 soldiers,2 and Umar Farouk Abdulmutallab, the failed suicide bomber who sought to destroy an airliner bound for Detroit on Christmas Day 2009.3 Aulaqi is also suspected of playing a role in the November 2010 AQAP plot to dispatch parcel bombs to the U.S. in cargo planes.

AQAP, estimated to have had as many as 4,000 members in 2015,4 has greatly expanded in the chaos of Yemen’s civil war, particularly since the overthrow of Yemen’s government by Iran-backed Houthi rebels in 2015. AQAP has exploited alliances with powerful, well-armed Yemeni tribes (including the Aulaq tribe from which Osama bin Laden and the radical cleric Aulaqi claimed descent) to establish sanctuaries and training bases in Yemen’s rugged mountains. This is similar to al-Qaeda’s modus operandi in Afghanistan before 9/11 and in Pakistan today. In April 2015, AQAP seized the city of al Mukalla and expanded its control of rural areas in southern Yemen. After AQAP withdrew in April 2016, the city was recaptured by pro-government Yemeni troops and troops from the United Arab Emirates (UAE), a member of the Saudi-led coalition that intervened in March 2015 in support of the Yemeni government. AQAP remains a potent force in Yemen.

The Islamic State (IS), formerly known as the Islamic State of Iraq and Syria (ISIS) or the Islamic State in Iraq and the Levant (ISIL), and before that as the Islamic State of Iraq and Al-Qaeda in Iraq, emerged as an al-Qaeda splinter group but has outstripped its parent organization in terms of the threats it poses to U.S. national interests. It seeks to overthrow the governments of Iraq, Syria, Lebanon, and Jordan and establish a nominal Islamic state governed by a harsh and brutal interpretation of Islamic law that is an existential threat to Christians, Shiite Muslims, Yazidis, and other religious minorities. Its long-term goals are to launch what it considers a jihad (holy war) to drive Western influence out of the Middle East; destroy Israel; diminish and discredit Shia Islam, which it considers apostasy; and become the nucleus of a global Sunni Islamic empire.

The Islamic State is composed of Sunni Muslims drawn to radical Islamist ideology. U.S. intelligence officials estimated in May 2016 that it commanded between 19,000 and 25,000 fighters in Iraq and Syria even after suffering extensive losses.5 Most of its members are Iraqi and Syrian Arabs, although it also has attracted more than 25,000 foreign fighters who have joined its ranks on a temporary or permanent basis, including at least 6,000 from Tunisia, 2,275 from Saudi Arabia, 2,000 from Jordan, 1,700 from Russia, 1,550 from France, 1,400 from Turkey, and 1,200 from Lebanon.6 Many of the foreign fighters have been killed or fled from Iraq and Syria as IS has been pushed back on several fronts.

The group was established as Al-Qaeda in Iraq (AQI) in 2004 by Abu Musab al-Zarqawi, a Palestinian Islamist extremist born in Jordan who fought in Afghanistan against the Soviet invasion. He was a close associate of Osama bin Laden, although he did not formally join al-Qaeda until 2004 when he was recognized as the leader of AQI. His organization has always taken a harder line against Shiites, whom it denigrates as apostates who deserve death, than has other franchises of the al-Qaeda network.

Zarqawi was killed in a U.S. air strike in 2006, and his organization was decimated by a U.S.-led counterterrorism campaign. The group made a comeback in Iraq after the withdrawal of U.S. troops in 2011 took the pressure off it and Iraqi Prime Minister Nouri al-Maliki’s Shia-dominated government alienated Sunni Iraqis, driving many of them to see ISIS as the lesser evil.

The IS began as a branch of al-Qaeda before it broke away from the core al-Qaeda leadership in 2013 in a dispute over leadership of the jihad in Syria. The IS shares a common ideology with its al-Qaeda parent organization but differs with respect to how to apply that ideology. It now rejects the leadership of bin Laden’s successor, Ayman al-Zawahiri, who criticized its extreme brutality, which has alienated many Muslims. This is a dispute about tactics and strategies, not long-term goals. It may also be prompted by a personal rivalry between Zawahiri and IS leader Abu Bakr al-Baghdadi, who sees himself as bin Laden’s true successor and the leader of a new generation of jihadists. Baghdadi also declared the formation of a caliphate with himself as the leader in June 2014, a claim that al-Qaeda rejects as illegitimate.

In 2014, the IS greatly expanded its control of a wide swath of western Iraq and eastern Syria, territory that it can use as a launching pad for operations in the heart of the Arab world and beyond. By May 2016, the United States and its allies had reduced the territory controlled by the Islamic State at its zenith by 45 percent in Iraq and 20 percent in Syria,7 But the IS continued to expand elsewhere, particularly in Libya, Egypt, Yemen, Afghanistan, Bangladesh, and Pakistan. Boko Haram, the Nigeria-based Islamist terrorist group, also pledged allegiance to the IS in March 2015.

The Islamic State poses a primarily regional threat. It has launched terrorist attacks inside Egypt, Jordan, Kuwait, Lebanon, Libya, Saudi Arabia, Tunisia, and Turkey, among other countries. It also claimed responsibility for the October 31, 2015, downing of a Russian passenger jet over Egypt’s Sinai Peninsula that killed 224 people.

The Islamic State’s early success in attracting the support of foreign militants, including at least 4,500 from Western countries and at least 250 from the United States, has amplified its potential threat as these foreign supporters, many of whom received military training, return home.8 IS foreign fighters teamed with local Islamist militants to launch terrorist attacks that killed 130 people in Paris, France, in November 2015 and 32 people in Brussels, Belgium, in March 2016, as well as a string of smaller attacks.

IS leader al-Baghdadi threatened to strike “in the heart” of America in July 2012.9 The IS reportedly has tried to recruit Americans who have joined the fighting in Syria and would be in a position to carry out this threat after returning to the United States.10 It also has inspired several terrorist attacks by self-radicalized “stray dogs” or “lone wolves” who have acted in its name, such as the foiled May 3, 2015, attack by two Islamist extremists who were fatally shot by police before they could commit mass murder in Garland, Texas; the July 16, 2015, shootings that killed four Marines and a sailor in Chattanooga, Tennessee; the December 2, 2015, shootings that killed 14 people in San Bernardino, California; and the June 12, 2016, shootings at a nightclub in Orlando, Florida, that killed 49 people. Such terrorist attacks, incited but not directed by the IS, are likely to continue for the foreseeable future.

The al-Nusra Front, al-Qaeda’s official affiliate in Syria, has an estimated 5,000 to 10,000 members and has emerged as one of the top two or three rebel groups fighting Syria’s Assad dictatorship.11 It was established as an offshoot of Al-Qaeda in Iraq (now renamed the Islamic State) in late 2011 by Abu Muhammad al-Julani, a lieutenant of AQI leader Abu Bakr al-Baghdadi.12 It has adopted a more pragmatic course than its extremist parent organization and has cooperated with moderate Syrian rebel groups against the Assad regime, as well as against the Islamic State.

When Baghdadi unilaterally proclaimed the merger of his organization and al-Nusra in April 2013 to form the Islamic State of Iraq and Syria, Julani rejected the merger and renewed his pledge to al-Qaeda leader Ayman al-Zawahiri. The two groups have clashed repeatedly, causing an estimated 3,000 deaths by March 2014.13

Al-Nusra has focused its attention on overthrowing the Syrian regime and has not emphasized its hostility to the United States, but that could easily change if it consolidates power within Syria. It already poses a potential threat because of its recruitment of a growing number of foreign Islamist militants, including some from Europe and the United States. According to U.S. officials, al-Qaeda leader al-Zawahiri dispatched a cadre of experienced al-Qaeda operatives to Syria, where they were embedded with al-Nusra and charged with organizing terrorist attacks against Western targets. Many members of the group, estimated to number in the dozens, were veterans of al-Qaeda’s operations in Afghanistan and Pakistan (part of what was called Khorasan in ancient times) and were referred to as the “Khorasan group” by U.S. officials.14

An American Muslim recruited by al-Nusra, Moner Mohammad Abusalha, conducted a suicide truck bombing in northern Syria on May 25, 2014, the first reported suicide attack by an American in Syria.15 At least five men have been arrested inside the United States for providing material assistance to al-Nusra, including Abdirahman Sheik Mohamud, a naturalized U.S. citizen born in Somalia who was arrested in April 2015 after returning from training in Syria, possibly to launch a terrorist attack inside the United States.16 The Khorasan group was targeted by a series of U.S. air strikes in 2014–2015 that degraded its capacity to organize terrorist attacks in Western countries. By mid-2015, the FBI assessed that the Islamic State had eclipsed al-Nusra as a threat to the U.S. homeland.17

FBI Director James Comey has stated that tracking Americans who have returned from Syria is one of the FBI’s top counterterrorism priorities.18 Then-Attorney General Eric Holder urged his international counterparts to block the flow of thousands of foreign fighters to Syria, which he termed “a cradle of violent extremism.” Speaking at a conference in Norway in July 2014, Holder warned:

We have a mutual and compelling interest in developing shared strategies for confronting the influx of U.S.-[born] and European-born violent extremists into Syria. And because our citizens can freely travel, visa free, from the U.S. to Norway and other European states—and vice versa—the problem of fighters in Syria returning home to any of our countries is a problem for all of our countries.19

Al-Qaeda in the Islamic Maghreb (AQIM), one of al-Qaeda’s weaker franchises before the Arab Spring uprisings began in 2011, has flourished in recent years in North Africa and is now one of al-Qaeda’s best-financed and most heavily armed elements. The 2011 overthrow of Libyan dictator Muammar Qadhafi pried open a Pandora’s box of problems that AQIM has exploited to bolster its presence in Algeria, Libya, Mali, Morocco, and Tunisia. AQIM accumulated large quantities of arms, including man-portable air defense systems (MANPADS), looted from Qadhafi’s huge arms depots.

The fall of Qadhafi also led hundreds of heavily armed Tuareg mercenaries formerly employed by his regime to cross into Mali, where they joined a Tuareg separatist insurgency against Mali’s weak central government. In November 2011, they formed the separatist National Movement for the Liberation of Azawad (MNLA) and sought to carve out an independent state. In cooperation with AQIM and the Islamist movement Ansar Dine, they gained control of northern Mali, a territory as big as Texas and the world’s largest terrorist sanctuary until the January 2013 French military intervention dealt a major setback to AQIM and its allies.

AQIM is estimated to have several hundred militants operating in Algeria, Libya, Mali, Niger, and Tunisia.20 Many AQIM cadres pushed out of Mali by the French intervention have regrouped in southwestern Libya and remain committed to advancing AQIM’s self-declared long-term goal of transforming the Sahel “into one vast, seething, chaotic Somalia.”21

The September 11, 2012, attack on the U.S. diplomatic mission in Benghazi underscored the extent to which Islamist extremists have grown stronger in the region, particularly in eastern Libya, a longtime bastion of Islamic fervor. The radical Islamist group that launched the attack, Ansar al-Sharia, has links to AQIM and shares its violent ideology. Ansar al-Sharia and scores of other Islamist militias have flourished in post-Qadhafi Libya because the weak central government has been unable to tame fractious militias, curb tribal and political clashes, or dampen rising tensions between Arabs and Berbers in the West and between Arabs and the Toubou tribe in the South.

AQIM does not pose as much of a threat to the U.S. homeland as other al-Qaeda offshoots pose, but it does threaten regional stability and U.S. allies in North Africa and Europe, where it has gained supporters and operates extensive networks for the smuggling of arms, drugs, and people.

WWTA: The WWTA reports that “Sunni violent extremism has been on an upward trajectory since the 1970s and has more groups, members, and safe havens than at any other point in history” and characterizes the Islamic State as “the preeminent terrorist threat because of its self-described caliphate in Syria and Iraq, its branches and emerging branches in other countries, and its increasing ability to direct and inspire attacks against a wide range of targets around the world.” The WWTA further assesses that al-Qaeda’s affiliates “are positioned to make gains in 2016, despite counterterrorism pressure that has largely degraded the network’s leadership in Afghanistan and Pakistan,” and that “US-based HVEs [homegrown violent extremists] will probably continue to pose the most significant Sunni terrorist threat to the US homeland in 2016.”22

Summary: Al-Qaeda offshoots based in the Middle East pose a growing threat to the U.S. homeland as a result of the recruitment of Muslim militants from Western countries, including the United States, and their efforts to inspire terrorist attacks by homegrown Islamist extremists.

Hezbollah Terrorism. Hezbollah (Party of God), the radical Lebanon-based Shiite revolutionary movement, poses a clear terrorist threat to international security. Hezbollah terrorists have murdered Americans, Israelis, Lebanese, Europeans, and citizens of many other nations. Originally founded in 1982, this Lebanese group has evolved from a local menace into a global terrorist network that is strongly backed by regimes in Iran and Syria, assisted by a political wing that has dominated Lebanese politics and funded by Iran and a web of charitable organizations, criminal activities, and front companies.

Hezbollah regards terrorism not only as a useful tool for advancing its revolutionary agenda, but also as a religious duty as part of a “global jihad.” It helped to introduce and popularize the tactic of suicide bombings in Lebanon in the 1980s, developed a strong guerrilla force and a political apparatus in the 1990s, provoked a war with Israel in 2006, intervened in the Syrian civil war after 2011 at Iran’s direction, and has become a major destabilizing influence in the ongoing Arab–Israeli conflict.

Hezbollah murdered more Americans than any other terrorist group before September 11, 2001. Despite al-Qaeda’s increased visibility since then, Hezbollah remains a bigger, better equipped, better organized, and potentially more dangerous terrorist organization, in part because it enjoys the support of the two chief state sponsors of terrorism in the world today: Iran and Syria. Hezbollah’s demonstrated capabilities led former Deputy Secretary of State Richard Armitage to dub it “the A-Team of Terrorists.”23

Hezbollah has expanded its operations from Lebanon to regional targets in the Middle East and then far beyond. It now is a global terrorist threat that draws financial and logistical support from its Iranian patrons as well as from the Lebanese Shiite diaspora in the Middle East, Europe, Africa, Southeast Asia, North America, and South America. Hezbollah fundraising and equipment procurement cells have been detected and broken up in the United States and Canada. Europe is believed to contain many more of these cells.

Hezbollah has been implicated in numerous terrorist attacks against Americans, including:

  • The April 18, 1983, bombing of the U.S. embassy in Beirut, which killed 63 people, including 17 Americans;
  • The October 23, 1983, suicide truck bombing of the Marine barracks at Beirut Airport, which killed 241 Marines and other personnel deployed as part of the multinational peacekeeping force in Lebanon;
  • The September 20, 1984, bombing of the U.S. embassy annex in Lebanon; and
  • The 1996 Khobar Towers bombing, which killed 19 American servicemen stationed in Saudi Arabia.

Hezbollah also was involved in the kidnapping of several dozen Westerners, including 14 Americans, who were held as hostages in Lebanon in the 1980s. The American hostages eventually became pawns that Iran used as leverage in the secret negotiations that led to the Iran–Contra affair in the mid-1980s.

Hezbollah has launched numerous attacks outside of the Middle East. It perpetrated the two deadliest terrorist attacks in the history of South America: the March 1992 bombing of the Israeli embassy in Buenos Aires, Argentina, which killed 29 people, and the July 1994 bombing of a Jewish community center in Buenos Aires that killed 96 people. The trial of those who were implicated in the 1994 bombing revealed an extensive Hezbollah presence in Argentina and other countries in South America.

Hezbollah has escalated its terrorist attacks against Israeli targets in recent years as part of Iran’s intensifying shadow war against Israel. In 2012, Hezbollah killed five Israeli tourists and a Bulgarian bus driver in a suicide bombing near Burgas, Bulgaria. Hezbollah terrorist plots against Israelis were foiled in Thailand and Cyprus during that same year.

In 2013, Hezbollah admitted that it had deployed several thousand militia members to fight in Syria on behalf of the Assad regime. By 2015, Hezbollah forces had become crucial in propping up the Assad regime after the Syrian army was hamstrung by casualties, defections, and low morale. Hezbollah also deployed personnel to Iraq after the 2003 U.S. intervention to assist pro-Iranian Iraqi Shia militias that were battling the U.S.-led coalition.

Although Hezbollah operates mostly in the Middle East, it has a global reach and has established a presence inside the United States. Hezbollah cells in the United States generally are focused on fundraising, including criminal activities such as those perpetrated by over 70 used-car dealerships identified as part of a scheme to launder hundreds of millions of dollars of cocaine-generated revenue that flowed back to Hezbollah.24

Covert Hezbollah cells could morph into other forms and launch terrorist operations inside the United States. Given Hezbollah’s close ties to Iran and its past record of executing terrorist attacks on Iran’s behalf, there is a real danger that Hezbollah terrorist cells could be activated inside the United States in the event of a conflict between Iran and the U.S. or Israel.

WWTA: The WWTA concludes that “Iran and Hizballah remain a continuing terrorist threat to U.S. interests and partners worldwide.”25

Summary: Hezbollah operates mostly in the Middle East, but it has established cells inside the United States that could be activated, particularly in the event of a military conflict with Iran, Hezbollah’s creator and chief backer.

Palestinian Terrorist Threats. A wide spectrum of Palestinian terrorist groups threaten Israel, including Fatah (al-Aqsa Martyrs Brigade); Hamas; Palestinian Islamic Jihad; the Popular Front for the Liberation of Palestine (PFLP); the Popular Front for the Liberation of Palestine–General Command (PFLP–GC); the Palestine Liberation Front; and the Army of Islam. Most of these groups are also hostile to the United States, which they denounce as Israel’s primary source of foreign support.

Although they are focused more on Israel and regional targets, these groups also pose a limited potential threat to the U.S. homeland, particularly should the Israeli–Palestinian peace process break down completely and the Palestinian Authority be dissolved. In the event of a military confrontation with Iran, Tehran also might seek to use Palestinian Islamic Jihad, the PFLP–GC, or Hamas as surrogates to strike the United States. Jihadist groups based in Gaza, such as the Army of Islam, also could threaten the U.S. homeland even if a terrorist attack there would set back Palestinian national interests. In general, however, Palestinian groups present a much bigger threat to Israel, Jordan, Egypt, and other regional targets than they do to the United States.

WWTA: The WWTA does not reference the potential threat of Palestinian terrorist attacks on the U.S. homeland.

Summary: Palestinian terrorist groups are focused primarily on Israeli targets and potentially on Egypt and Jordan, which are perceived as collaborating with Israel. They also, however, pose a limited potential threat to the U.S. homeland because of the possibility that, if the Israeli–Palestinian peace process broke down completely or Iran became involved in a military conflict with the U.S., Palestinian surrogates could be used to target the U.S. homeland.

Iran’s Ballistic Missile Threat. Iran has an extensive missile development program that has received key assistance from North Korea and more limited support from Russia and China before sanctions were imposed by the U.N. Security Council. The National Air and Space Intelligence Center noted in 2013 that:

Iran could develop and test an ICBM capable of reaching the United States by 2015. Since 2008, Iran has conducted multiple successful launches of the two-stage Safir space launch vehicle and has also revealed the larger two-stage Simorgh space launch vehicle, which could serve as a test bed for developing ICBM technologies.26

Although Tehran’s missile arsenal primarily threatens U.S. bases and allies in the region, Iran eventually could expand the range of its missiles to include the continental United States. In its January 2014 report on Iran’s military power, the Pentagon assessed that “Iran continues to develop technological capabilities that could be applicable to nuclear weapons and long-range missiles, which could be adapted to deliver nuclear weapons, should Iran’s leadership decide to do so.”27

WWTA: The WWTA assesses that “Iran’s ballistic missiles are inherently capable of delivering WMD, and Tehran already has the largest inventory of ballistic missiles in the Middle East.” In addition, “Iran’s progress on space launch vehicles—along with its desire to deter the United States and its allies—provides Tehran with the means and motivation to develop longer-range missiles, including ICBMs.”28

Summary: Iran’s ballistic missile force poses a regional threat to the U.S. and its allies, but Tehran eventually could expand the range of its missiles to threaten the continental United States.

Threat of Regional War

The Middle East region is one of the most complex and volatile threat environments faced by the United States and its allies. Iran, various al-Qaeda offshoots, Hezbollah, Arab–Israeli clashes, and a growing number of radical Islamist militias and revolutionary groups in Egypt, Iraq, Libya, Syria, and Yemen pose actual or potential threats to the U.S. and its allies.

Iranian Threats in the Middle East. Iran is an anti-Western revolutionary state that seeks to tilt the regional balance of power in its favor by driving out the Western presence, undermining and overthrowing opposing governments, and establishing its hegemony over the oil-rich Persian Gulf region. It also seeks to radicalize Shiite communities and advance their interests against Sunni rivals. Iran has a long record of sponsoring terrorist attacks against American allies and other interests in the region. With regard to conventional threats, Iran’s ground forces dwarf the relatively small armies of the other Gulf states, and its formidable ballistic missile forces pose significant threats to its neighbors.


The July 14, 2015, Iran nuclear agreement, which lifted nuclear-related sanctions on Iran in January 2016, gave Tehran access to about $100 billion in restricted assets and allowed it to expand its oil and gas exports, its chief source of state revenues. This sanctions relief will boost Iran’s economy and enable Iran to enhance its strategic position, military capabilities, and support for surrogate networks and terrorist groups. Tehran announced in May 2016 that it was increasing its military budget for 2016–2017 to $19 billion, a 90 percent increase over the previous year.29

The lifting of sanctions also has allowed Tehran to emerge from diplomatic isolation and strengthen strategic ties with Russia that will allow it to purchase advanced arms and modernize its military forces. Russian President Vladimir Putin traveled to Iran in November 2015 to meet with Ayatollah Khamenei, Iran’s Supreme Leader, and other officials. Both regimes called for enhanced military cooperation.

This growing strategic relationship could result in Iran’s largest arms imports since the 1979 revolution. Tehran announced in April 2016 that Russia had started deliveries of up to five S-300 Favorit long-range surface-to-air missile systems, which can track up to 100 aircraft and engage six of them simultaneously at a range of 200 kilometers.30 Moscow also began negotiations to sell Iran T-90 tanks and advanced Sukhoi Su-30 Flanker fighter jets.31 The warplanes will significantly improve Iran’s air defense and long-range strike capabilities.

After the nuclear agreement, Iran and Russia escalated their strategic cooperation in propping up Syria’s embattled Assad regime. Iran’s growing military intervention in Syria was partly eclipsed by Russia’s military intervention and launching of an air campaign against Assad’s enemies in September 2015, but Iran’s Islamic Revolutionary Guard Corps (IRGC) and surrogate groups have played the leading role in spearheading the ground offensives that clawed back territory from Syrian rebel groups and tilted the military balance in favor of the Assad regime. By October 2015, Iran had deployed an estimated 7,000 IRGC troops and paramilitary forces in Syria, along with an estimated 20,000 foreign fighters from Iran-backed Shiite militias from Lebanon, Iraq, Afghanistan, and Pakistan.32

Terrorist Attacks. Iran has adopted a political warfare strategy that emphasizes irregular warfare, asymmetric tactics, and the extensive use of proxy forces. The Islamic Revolutionary Guard Corps has trained, armed, supported, and collaborated with a wide variety of radical Shia and Sunni militant groups, as well as Arab, Palestinian, Kurdish, and Afghan groups that do not share its radical Islamist ideology. The IRGC’s elite Quds (Jerusalem) Force has cultivated, trained, armed, and supported numerous proxies, particularly the Lebanon-based Hezbollah; Iraqi Shia militant groups; Palestinian groups such as Hamas and Palestine Islamic Jihad; and groups that have fought against the governments of Afghanistan, Bahrain, Egypt, Israel, Iraq, Jordan, Kuwait, Saudi Arabia, Turkey, and Yemen.

Iran is the world’s foremost state sponsor of terrorism and has made extensive efforts to export its radical Shia brand of Islamist revolution. It has found success in establishing a network of powerful Shia revolutionary groups in Lebanon and Iraq; has cultivated links with Afghan Shia and Taliban militants; and has stirred Shia unrest in Bahrain, Iraq, Libya, Saudi Arabia, and Yemen. In recent years, Iranian arms shipments have been intercepted regularly by naval forces off the coasts of Bahrain and Yemen, and Israel has repeatedly intercepted arms shipments, including long-range rockets, bound for Palestinian militants in Gaza.

Mounting Missile Threat. Iran possesses the largest number of deployed missiles in the Middle East.33 The backbone of the Iranian ballistic missile force is formed by the Shahab series of road-mobile surface-to-surface missiles, which are based on Soviet-designed Scud missiles. The Shahab missiles are potentially capable of carrying nuclear, chemical, or biological warheads in addition to conventional high-explosive warheads. Their relative inaccuracy (compared to NATO ballistic missiles) limits their effectiveness unless they are employed against large, soft targets such as cities.

Iran’s heavy investment in such weapons has fueled speculation that the Iranians intend eventually to replace the conventional warheads in their longer-range missiles with nuclear warheads. The Nuclear Threat Initiative has concluded that “[r]egardless of the veracity of these assertions, Tehran indisputably possesses a formidable weapons delivery capability, and its ongoing missile program poses serious challenges to regional stability.”34

Iran is not a member of the Missile Technology Control Regime, and it has sought aggressively to acquire, develop, and deploy a wide spectrum of ballistic missile, cruise missile, and space launch capabilities. During the 1980–1988 Iran–Iraq war, Iran acquired Soviet-made Scud-B missiles from Libya and later acquired North Korean–designed Scud-C and No-dong missiles, which it renamed the Shahab-2 (with an estimated range of 500 kilometers or 310 miles) and Shahab-3 (with an estimated range of 900 kilometers or 560 miles). It now can produce its own variants of these missiles as well as longer-range Ghadr-1 and Qiam missiles.

Iran’s Shahab-3 and Ghadr-1, which is a modified version of the Shahab-3 with a smaller warhead but greater range (about 1,600 kilometers or 1,000 miles), are considered more reliable and advanced than the North Korean No-dong missile from which they are derived. The then-Director of the Defense Intelligence Agency, Lieutenant General Michael T. Flynn, warned in 2014 that:

Iran can strike targets throughout the region and into Eastern Europe. In addition to its growing missile and rocket inventories, Iran is seeking to enhance lethality and effectiveness of existing systems with improvements in accuracy and warhead designs. Iran is developing the Khalij Fars, an anti-ship ballistic missile which could threaten maritime activity throughout the Persian Gulf and Strait of Hormuz.35

Iran’s ballistic missiles pose a major threat to U.S. bases and allies from Turkey, Israel, and Egypt in the west to Saudi Arabia and the other Gulf states to the south and Afghanistan and Pakistan to the east. However, it is Israel, which has fought a shadow war with Iran and its terrorist proxies, that is most at risk from an Iranian attack. In case the Israeli government had any doubt about Iran’s implacable hostility, the Revolutionary Guards displayed a message written in Hebrew on the side of one of the Iranian missiles tested in March 2016: “Israel must be wiped off the earth.”36 The development of nuclear warheads for Iran’s ballistic missiles would seriously degrade Israel’s ability to deter attacks, an ability that the existing (but not officially acknowledged) Israeli monopoly on nuclear weapons in the Middle East currently provides.

For Iran’s radical regime, hostility to Israel, to which Iran sometimes refers as the “little Satan,” is second only to hostility to the United States, which the leader of Iran’s 1979 revolution, Ayatollah Khomeini, dubbed the “great Satan.” But Iran poses a greater immediate threat to Israel than it does to the United States, since Israel is a smaller country with fewer military capabilities and located much closer to Iran. It already is within range of Iran’s Shahab-3 missiles. Moreover, all of Israel can be hit with the thousands of shorter-range rockets that Iran has provided to Hezbollah in Lebanon and to Hamas and Palestine Islamic Jihad in Gaza.

Weapons of Mass Destruction. Tehran has invested tens of billions of dollars since the 1980s in a nuclear weapons program that was masked within its civilian nuclear power program. It built clandestine underground facilities to enrich uranium, which were subsequently discovered near Natanz and Fordow, and is building a heavy-water reactor near Arak that will give it a second potential route to nuclear weapons.37

As of June 2015, Iran had accumulated enough low-enriched uranium to build eight nuclear bombs if enriched to weapons-grade levels, and it could enrich enough uranium to arm one bomb in less than two months.38 Clearly, the development of an Iranian nuclear bomb would greatly amplify the threat posed by Iran. Even if Iran did not use a nuclear weapon or pass it on to one of its terrorist surrogates to use, the regime in Tehran could become emboldened to expand its support for terrorism, subversion, and intimidation, assuming that its nuclear arsenal would protect it from retaliation as has been the case with North Korea.

On July 14, 2015, President Barack Obama announced that the United States and Iran, with China, France, Germany, Russia, the United Kingdom, and the European Union High Representative for Foreign Affairs and Security Policy, had reached a “comprehensive, long-term deal with Iran that will prevent it from obtaining a nuclear weapon.”39 The agreement, however, did a much better job of dismantling sanctions against Iran than it did of dismantling Iran’s nuclear infrastructure.

In fact, the agreement did not require that any of the illicit facilities that Iran covertly built be dismantled. Tehran was allowed to continue use of its uranium enrichment facilities at Natanz and Fordow, although the latter facility is to be repurposed at least temporarily as a research site. The heavy-water reactor at Arak was also retained with modifications that will reduce its yield of plutonium. All of these facilities, built covertly and housing operations prohibited by multiple U.N. Security Council Resolutions (UNSCRs), have been legitimized by the agreement.

Under the agreement, Tehran not only gets to keep all of its illicit nuclear facilities, but also merely has to mothball—not destroy—centrifuges used to enrich uranium. This means that Iran can quickly expand its enrichment activities and rapidly shorten its nuclear breakout timeline when restrictions on the number of centrifuges and uranium enrichment levels expire in 10 to 15 years.

Iran can quickly reverse all of its concessions if it decides to renege on the deal in the future. Sanctions on Iran, however, especially at the U.N., will not “snap back” into place, but will take considerable time to re-impose and take effect—assuming that they can be reimposed at all. If the Russians or Chinese were to object, it would further delay the inherent time lag before sanctions could have any significant effect and might even derail U.N. sanctions completely.

The Iran nuclear agreement marked a risky departure from more than five decades of U.S. nonproliferation efforts under which Washington opposed the spread of sensitive nuclear technologies, such as uranium enrichment, even for allies. Iran got a better deal on uranium enrichment under the agreement than such U.S. allies as the United Arab Emirates, South Korea, and Taiwan have received from Washington in the past. In fact, the Obama Administration gave Iran better terms on uranium enrichment than the Ford Administration gave to the Shah of Iran, a close U.S. ally before the 1979 revolution.

Although Washington has downplayed the risks inherent in the nuclear agreement, worried governments in the region are bound to take out insurance policies against a nuclear Iran in the form of their own nuclear programs. This could spur a cascade of nuclear proliferation from threatened states such as Saudi Arabia, Egypt, Turkey, and the UAE. Saudi officials already have announced plans for building up to 16 nuclear power plants by 2040. The Saudi government signed agreements with Rosatom, Russia’s state-run nuclear company, in June 2015 and with China in January 2016 that will significantly advance the Saudi nuclear program,40 And Egypt signed a November 2015 agreement with Russia to build four nuclear reactors. Although these are civilian nuclear programs, they could be used to mask a push for nuclear weapons, as happened in Iran.

Iran is a declared chemical weapons power that claims to have destroyed all of its chemical weapons stockpiles. U.S. intelligence agencies assess that Iran maintains the capability to produce chemical warfare (CW) agents and “probably” has the capability to produce some biological warfare agents for offensive purposes if it should decide to do so.41 Iran also has threatened to disrupt the flow of Persian Gulf oil exports by closing the Strait of Hormuz in the event of a conflict with the U.S. or its allies.

WWTA: The WWTA assesses that Iran “presents an enduring threat to US national interests because of its support to regional terrorist and militant groups and the Asad regime, as well as its development of advanced military capabilities.” Its “intent is to thwart US, Saudi, and Israeli influence, bolster its allies, and fight ISIL’s expansion. Tehran might even use American citizens detained when entering Iranian territories as bargaining pieces to achieve financial or political concessions in line with their strategic intentions.”42

With respect to the nuclear issue, the WWTA assesses that “Iran probably views the Joint Comprehensive Plan of Action (JCPOA) as a means to remove sanctions” and “to eventually expand its nuclear infrastructure.” In addition, “Iran’s overarching strategic goals…have led it to pursue capabilities to meet its nuclear energy and technology goals and give it the ability to build missile-deliverable nuclear weapons….”43

Summary: Iran poses a major potential threat to U.S. bases, interests, and allies in the Middle East by virtue of its ballistic missile capabilities, continued nuclear ambitions, long-standing support for terrorism, and extensive support for Islamist revolutionary groups.

Arab Attack on Israel. In addition to threats from Iran, Israel faces the constant threat of attack from Palestinian, Lebanese, Egyptian, Syrian, and other Arab terrorist groups. The threat posed by Arab states, which lost four wars against Israel in 1948, 1956, 1967, and 1973 (Syria and the PLO lost a fifth war in 1982 in Lebanon), has gradually declined. Egypt and Jordan have signed peace treaties with Israel. Iraq, Libya, and Syria have disintegrated in increasingly brutal civil wars. Although the conventional military threat to Israel from Arab states has declined, the unconventional military and terrorist threats, especially from an expanding number of sub-state actors, have risen substantially.

Iran has systematically bolstered many of these groups, even if it did not necessarily share their ideology. Today, Iran’s surrogates, Hezbollah and Palestinian Islamic Jihad, along with Hamas, a more distant ally, pose the chief immediate threats to Israel. After Israel’s May 2000 withdrawal from southern Lebanon and the September 2000 outbreak of fighting between Israelis and Palestinians, Hezbollah stepped up its support for such Palestinian extremist groups as Hamas, Palestinian Islamic Jihad, the al-Aqsa Martyrs’ Brigades, and the Popular Front for the Liberation of Palestine. It also expanded its own operations in the West Bank and Gaza and provided funding for specific attacks launched by other groups.

In July 2006, Hezbollah forces crossed the Lebanese border in an effort to kidnap Israeli soldiers inside Israel, igniting a military clash that claimed hundreds of lives and severely damaged the economies on both sides of the border. Hezbollah has since rebuilt its depleted arsenal with help from Iran and Syria. Israeli officials estimate that Hezbollah has amassed around 150,000 rockets, including a number of long-range Iranian-made missiles capable of striking cities throughout Israel.44

Since Israel’s withdrawal from the Gaza Strip in 2005, Hamas, Palestinian Islamic Jihad, and other terrorist groups have fired more than 11,000 rockets into Israel, sparking wars in 2008–2009, 2012, and 2014.45 Over 5 million Israelis out of a total population of 8.1 million live within range of rocket attacks from Gaza, although the successful operation of the Iron Dome anti-missile system greatly mitigated this threat during the Gaza conflict in 2014. In that war, Hamas also unveiled a sophisticated tunnel network that it used to infiltrate Israel to launch attacks on Israeli civilians and military personnel.

Israel also faces a growing threat of terrorist attacks from Syria. Islamist extremist groups fighting the Syrian government, including the al-Qaeda–affiliated al-Nusra Front, have attacked Israeli positions in the Golan Heights, which Israel captured in the 1967 Arab–Israeli war.

WWTA: The WWTA does not reference Arab threats to Israel.

Summary: The threat posed to Israel by Arab states has declined in recent years as a result of the overthrow or weakening of hostile Arab regimes in Iraq and Syria. However, there is a growing threat from sub-state actors such as Hamas, Hezbollah, the Islamic State, and other terrorist groups in Egypt, Gaza, Lebanon, and Syria. Given the region’s inherent volatility, the general destabilization that has occurred as a consequence of Syria’s civil war, the growth of the Islamic State as a major threat actor, and the United States’ long-standing support for Israel, any concerted attack on Israel would be a major concern for the U.S.

Terrorist Threats from Hezbollah. Hezbollah is a close ally of, frequent surrogate for, and terrorist subcontractor for Iran’s revolutionary Islamist regime. Iran played a crucial role in creating Hezbollah in 1982 as a vehicle for exporting its revolution, mobilizing Lebanese Shia, and developing a terrorist surrogate for attacks on its enemies.

Tehran provides the bulk of Hezbollah’s foreign support: arms, training, logistical support, and money. Iran provides at least $100 million in annual financial support for Hezbollah, and some experts estimate that this could run as high as $200 million annually.46 Tehran has lavishly stocked Hezbollah’s expensive and extensive arsenal of rockets, sophisticated land mines, small arms, ammunition, explosives, anti-ship missiles, anti-aircraft missiles, and even unmanned aerial vehicles (UAVs) that Hezbollah can use for aerial surveillance or remotely piloted terrorist attacks. Iranian Revolutionary Guards have trained Hezbollah terrorists in Lebanon’s Bekaa Valley and in Iran.

Iran has used Hezbollah as a club to hit not only Israel and Tehran’s Western enemies, but also many Arab countries. Iran’s revolutionary ideology has fueled its hostility to other Middle Eastern states, many of which it seeks to overthrow and replace with radical allies. During the Iran–Iraq war, Iran used Hezbollah to launch terrorist attacks against Iraqi targets and against Arab states that sided with Iraq. Hezbollah launched numerous terrorist attacks against Saudi Arabia and Kuwait, which extended strong financial support to Iraq’s war effort, and participated in several other terrorist operations in Bahrain and the United Arab Emirates.

Iranian Revolutionary Guards conspired with the branch of Hezbollah in Saudi Arabia to conduct the 1996 Khobar Towers bombing in Saudi Arabia. Hezbollah collaborated with the IRGC’s Quds Force to destabilize Iraq after the 2003 U.S. occupation. It also helped to train and advise the Mahdi Army, the radical anti-Western Shiite militia led by militant cleric Moqtada al-Sadr.

Hezbollah threatens the security and stability of the Middle East and Western interests in the Middle East on a number of fronts. In addition to its murderous actions against Israel, Hezbollah has used violence to impose its radical Islamist agenda and subvert democracy in Lebanon. Although some experts believed that Hezbollah’s participation in the 1992 Lebanese elections and subsequent inclusion in Lebanon’s parliament and coalition governments would moderate its behavior, its political inclusion did not lead it to renounce terrorism.

Hezbollah also poses a potential threat in Europe to America’s NATO allies. Hezbollah established a presence inside European countries in the 1980s amid the influx of Lebanese citizens seeking to escape Lebanon’s civil war. It took root among Lebanese Shiite immigrant communities throughout Europe. German intelligence officials estimate that roughly 900 Hezbollah members live in Germany alone. Hezbollah also has developed an extensive web of fundraising and logistical support cells throughout Europe.47

France and Britain have been the principal European targets of Hezbollah terrorism, in part because both countries opposed Hezbollah’s agenda in Lebanon and were perceived as enemies of Iran, Hezbollah’s chief patron. Hezbollah has been involved in many terrorist attacks against Europeans, including:

  • The October 1983 bombing of the French contingent of the multinational peacekeeping force in Lebanon (on the same day as the U.S. Marine barracks bombing), which killed 58 French soldiers;
  • The December 1983 bombing of the French embassy in Kuwait;
  • The April 1985 bombing of a restaurant near a U.S. base in Madrid, Spain, which killed 18 Spanish citizens;
  • A campaign of 13 bombings in France in 1986 that targeted shopping centers and railroad facilities, killing 13 people and wounding more than 250; and
  • A March 1989 attempt to assassinate British novelist Salman Rushdie that failed when a bomb exploded prematurely, killing a terrorist in London.

Hezbollah attacks in Europe trailed off in the 1990s after Hezbollah’s Iranian sponsors accepted a truce in their bloody 1980–1988 war with Iraq and no longer needed a surrogate to punish states that Tehran perceived as supporting Iraq. Significantly, the participation of European troops in Lebanese peacekeeping operations, which became a lightning rod for Hezbollah terrorist attacks in the 1980s, could become an issue again if Hezbollah attempts to revive its aggressive operations in southern Lebanon. Troops from European Union member states may someday find themselves attacked by Hezbollah with weapons financed by Hezbollah supporters in their home countries.

As of 2015, Hezbollah operatives were deployed in countries throughout Europe, including Belgium, Bulgaria, Cyprus, France, Germany, and Greece.48

WWTA: The WWTA assesses that “Iran and Hizballah remain a continuing terrorist threat to U.S. interests and partners worldwide.”49

Summary: Hezbollah poses a major potential terrorist threat to the U.S. and its allies in the Middle East and Europe.

Al-Qaeda: A Continuing Regional Threat. The Arab Spring uprisings that began in 2011 have created power vacuums that al-Qaeda, the Islamic State, and other Islamist extremist groups have exploited to advance their hostile agendas. The al-Qaeda network has taken advantage of failed or failing states in Iraq, Libya, Mali, Syria, and Yemen. The fall of autocratic Arab regimes and the subsequent factional infighting within the ad hoc coalitions that ousted them created anarchic conditions that have enabled al-Qaeda franchises to expand the territories that they control. Rising sectarian tensions resulting from conflicts in Iraq, Syria, and Yemen also have presented al-Qaeda and other Sunni extremist groups with major opportunities to expand their activities.

Jonathan Evans, Director General of the British Security Service (MI5), has warned that “parts of the Arab world have once more become a permissive environment for al-Qaeda.”50 In Egypt, Libya, Syria, Tunisia, and Yemen, the collapse or purge of intelligence and counterterrorism organizations removed important constraints on the growth of al-Qaeda and similar Islamist terrorist groups. Many dangerous terrorists were released or escaped from prison. Al-Qaeda and other revolutionary groups were handed new opportunities to recruit, organize, attract funding for, train, and arm a new wave of followers and to consolidate safe havens from which to mount future attacks.

The Arab Spring uprisings were a golden opportunity for al-Qaeda, coming at a time when its sanctuaries in Pakistan had become increasingly threatened by U.S. drone strikes. Given al-Qaeda’s Arab roots, the Middle East and North Africa provide much better access to potential Arab recruits than is provided by the more distant and remote regions along the Afghanistan–Pakistan border, where many al-Qaeda cadres fled after the fall of the Taliban regime in Afghanistan in 2001. The countries destabilized by the Arab uprisings also could provide easier access to al-Qaeda’s Europe-based recruits, who pose dangerous threats to the U.S. homeland by virtue of their European passports and greater ability to blend into Western societies.

WWTA: The WWTA assesses that affiliates of al Qaeda “are positioned to make gains in 2016, despite counterterrorism pressure that has largely degraded the network’s leadership in Afghanistan and Pakistan,” and “will continue to pose a threat to local, regional, and even possibly global interests…. Other Sunni terrorist groups retain the ability to attract recruits and resources.”51

Summary: The al-Qaeda network and the Islamic State have exploited the political turbulence of the Arab Spring to expand their strength and control of territory in the Middle East. They pose growing regional threats to the U.S. and its allies.

Growing Threats to Jordan. Jordan, a key U.S. ally, faces external threats from Syria’s Assad regime and from Islamist extremists, including the Islamic State, who have carved out sanctuaries in Syria and Iraq. Jordan’s cooperation with the United States, Saudi Arabia, and other countries in the 2014–2015 air campaign against the IS in Syria and in supporting moderate elements of the Syrian opposition has angered both the Assad regime and Islamist extremist rebels. Damascus could retaliate for Jordanian support for Syrian rebels with cross-border attacks, air strikes, ballistic missile strikes, or the use of terrorist attacks by such surrogates as Hezbollah or the PFLP–GC.

The Islamic State is committed to overthrowing the government of Jordan and replacing it with an Islamist dictatorship. In its previous incarnation as al-Qaeda in Iraq, the IS mounted attacks against targets in Jordan that included the November 2005 suicide bombings at three hotels in Amman that killed 57 people.52 The IS also burned to death a Jordanian Air Force pilot captured in Syria after his plane crashed and released a video of his grisly murder in February 2015. Jordan also faces threats from Hamas and from Jordanian Islamist extremists, particularly some based in the southern city of Maan who organized pro-IS demonstrations in 2014. Although Jordanian security forces have successfully foiled several IS terrorist plots, six Jordanian border guards were killed by a car bomb on June 21, 2016, prompting Jordan to close the border.

WWTA: The WWTA does not reference threats to Jordan.

Summary: Jordan faces rising security threats from the Islamic State, which has expanded its control of territory in neighboring Syria and Iraq. Because Jordan is one of the very few Arab states that maintain a peaceful relationship with Israel and has been a key regional partner in fighting Islamist terrorism, its destabilization would be a troubling development.

Terrorist Attacks on and Possible Destabilization of Egypt. The 2011 ouster of President Hosni Mubarak’s regime undermined the authority of Egypt’s central government and allowed disgruntled Bedouin tribes, Islamist militants, and smuggling networks to grow stronger and bolder in Egypt’s Sinai Peninsula. President Mohamed Morsi’s Muslim Brotherhood–backed government, elected to power in 2012, took a relaxed attitude toward Hamas and other Gaza-based Islamist extremists, enabling Islamist militants in the Sinai to grow even stronger with support from Gaza. They carved out a staging area in the remote mountains of the Sinai that they have used as a springboard for attacks on Israel, Egyptian security forces, tourists, the Suez Canal, and a pipeline carrying Egyptian natural gas to Israel and Jordan.

The July 2013 coup against Morsi resulted in a military government that took a much harder line against the Sinai militants, but it also raised the ire of more moderate Islamists, who could turn to terrorism to avenge Morsi’s fall. Terrorist attacks, which had been limited to the Sinai, expanded in lethality and intensity to include bomb attacks in Cairo and other cities by early 2014. In November 2014, the Sinai-based terrorist group Ansar Bayt al-Maqdis (Supporters of Jerusalem) declared its allegiance to the Islamic State and renamed itself the Sinai Province of the Islamic State. It has launched a growing terrorist campaign against the Egyptian army, police, and other government institutions. It also claimed responsibility for the October 31, 2015, bombing of a Russian passenger plane flying to Saint Petersburg from Sharm-el-Sheikh that killed 224 people.

Egypt also faces potential threats from Islamist militants and al-Qaeda affiliates based in Libya. The Egyptian air force bombed Islamic State targets in Libya on February 16, 2015, the day after the terrorist organization released a video showing the decapitation of 21 Egyptian Christians who had been working in Libya. Egypt has stepped up security operations along the border with Libya to block the smuggling of arms and militants into Egypt. Cairo also has supported Libyans fighting Islamist extremists in eastern Libya.

During the 2014 conflict between Hamas and Israel, Egypt closed tunnels along the Gaza–Sinai border that have been used to smuggle goods, supplies, and weapons into Gaza. It has continued to uncover and destroy tunnels to disrupt an important source of external support for Sinai Province terrorists. Egypt has continued to uphold its peace treaty with Israel and remains an important ally against Islamist terrorist groups.

WWTA: The WWTA assesses that “Egypt faces a persistent threat of terrorist and militant activity directed primarily at state security forces in both the Sinai Peninsula and in mainland Egypt. The security services have initiated a counterterrorism campaign to disrupt and detain Sinai-based militants; however, terrorist groups still retain the ability to conduct attacks.” The ongoing terrorist threat “places further strain on Egypt’s economy by harming Egypt’s tourism industry, a key source of revenue. The country is also grappling with high poverty and unemployment rates.”53

Summary: Egypt is threatened by Islamist extremist groups that have established bases in the Sinai Peninsula, Gaza, and Libya. Left unchecked, these groups could foment greater instability not only in Egypt, but also in neighboring countries.

Threats to Saudi Arabia and Other Members of the Gulf Cooperation Council. Saudi Arabia and the five other Arab Gulf states—Bahrain, Kuwait, Oman, Qatar, and the United Arab Emirates—formed the Gulf Cooperation Council (GCC) in 1981 to deter and defend against Iranian aggression. Iran remains the primary external threat to their security. Tehran has supported groups that launched terrorist attacks against Bahrain, Kuwait, Saudi Arabia, and Yemen. It sponsored the Islamic Front for the Liberation of Bahrain, a surrogate group that plotted a failed 1981 coup against Bahrain’s ruling Al Khalifa family, the Sunni rulers of the predominantly Shia country. Iran also has long backed Bahraini branches of Hezbollah and the Dawa Party.

When Bahrain was engulfed in a wave of Arab Spring protests in 2011, its government charged that Iran again exploited the protests to back the efforts of Shia radicals to overthrow the royal family. Saudi Arabia, fearing that a Shia revolution in Bahrain would incite its own restive Shia minority, led a March 2011 GCC intervention that backed Bahrain’s government with about 1,000 Saudi troops and 500 police from the United Arab Emirates.

Bahrain has intercepted several shipments of Iranian arms, including sophisticated bombs employing explosively formed penetrators (EFPs). The government withdrew its ambassador to Tehran when two Bahrainis with ties to the IRGC were arrested after their arms shipment was intercepted off Bahrain’s coast in July 2015. Iranian hardliners have steadily escalated pressure on Bahrain. In March 2016, a former IRGC general who is a close adviser to Ayatollah Khamenei stated that “Bahrain is a province of Iran that should be annexed to the Islamic Republic of Iran.”54 After Bahrain stripped the citizenship of a senior Shiite cleric, Sheikh Isa Qassim, General Qassim Suleimani, the commander of the IRGC’s Quds Force, threatened to make Bahrain’s royal family “pay the price and disappear.”55

Saudi Arabia also has criticized Iran for its support for radical Saudi Shiites, its intervention in Syria, and its support for Shiite Islamists in Lebanon, Iraq, and Yemen. In January 2016, Saudi Arabia executed a Shiite cleric charged with sparking anti-government protests and cut diplomatic ties with Iran after Iranian mobs enraged by the execution attacked and set fire to the Saudi embassy in Tehran.

Saudi Arabia also faces threats from Islamist extremists, including al-Qaeda offshoots in Iraq and Yemen that have attracted many Saudi recruits. Al-Qaeda launched a series of bombings and terrorist attacks inside the kingdom in 2003 and a major attack on the vital Saudi oil facility in Abqaiq in 2006, but a security crackdown drove many of its members out of the country by the end of the decade. Many of them joined Al-Qaeda in the Arabian Peninsula in neighboring Yemen. AQAP has flourished, aided by the instability fostered by Arab Spring protests and the ouster of the Yemeni government by Iran-backed Houthi rebels in early 2015.

In addition to terrorist threats and possible rebellions by Shia or other disaffected internal groups, Saudi Arabia and the other GCC states face possible military threats from Iran. Tehran is unlikely to launch direct military attacks against these countries because of their close security ties with the United States, but it has backed Shiite terrorist groups within GCC states such as Saudi Hezbollah and has supported the Shiite Houthi rebels in Yemen. In March 2015, Saudi Arabia led a 10-country coalition that launched an air campaign against Houthi forces and provided support for ousted Yemeni President Abdu Rabu Mansour Hadi, who took refuge in Saudi Arabia. The Saudi Navy also established a blockade of Yemeni ports to prevent Iran from aiding the rebels.

WWTA: The WWTA assesses that “Tehran views itself as leading the ‘axis of resistance’—which includes the Asad regime and subnational groups aligned with Iran, especially Lebanese Hizballah and Iraqi Shia militants. Their intent is to thwart US, Saudi, and Israeli influence, bolster its allies, and fight ISIL’s expansion.”56

Summary: Saudi Arabia and other members of the Gulf Cooperation Council face continued threats from Iran as well as rising threats from Islamist extremist groups such as al-Qaeda, the Islamic State, and Houthi militias in Yemen. Though Saudi citizens and Islamic charities have supported Islamist extremist groups and the Saudi government promulgates the religious views of the fundamentalist Wahhabi sect of Sunni Islam, the Saudi government also serves to check radical Islamist groups like the Islamic State and is a regional counterbalance to Iran.

Threats to the Commons

The United States has critical interests at stake in the Middle Eastern commons: sea, air, space, and cyber. The U.S. has long provided the security backbone in these areas, which in turn has supported the region’s economic development and political stability.

Maritime. Maintaining the security of the sea lines of communication in the Persian Gulf, Arabian Sea, Red Sea, and Mediterranean Sea is a high priority for strategic, economic, and energy security purposes. The Persian Gulf region contains approximately 50 percent of the world’s oil reserves and is a crucial source of oil and gas for energy-importing states, particularly China, India, Japan, South Korea, and many European countries. The flow of that oil could be interrupted by interstate conflict or terrorist attacks.


Bottlenecks such as the Strait of Hormuz, the Suez Canal, and the Bab el-Mandeb Strait are potential choke points for restricting the flow of oil, international trade, and the deployment of U.S. Navy warships. The chief potential threat to the free passage of ships through the Strait of Hormuz, one of the world’s most important maritime choke points, is Iran. Approximately 17 million barrels of oil a day—roughly 30 percent of the seaborne oil traded worldwide—flowed through the strait in 2013.57

Iran has trumpeted the threat it could pose to the free flow of oil exports from the Gulf if it is attacked or threatened with a cutoff of its own oil exports. Iran’s leaders have threatened to close the Strait of Hormuz, the jugular vein through which most Gulf oil exports flow to Asia and Europe. Although the United States has greatly reduced its dependence on oil exports from the Gulf, it still would sustain economic damage in the event of a spike in world oil prices, and many of its European and Asian allies and trading partners import a substantial portion of their oil needs from the region. Iran’s Supreme Leader, Ayatollah Ali Khamenei, has repeatedly played up Iran’s threat to international energy security, proclaiming in 2006 that “[i]f the Americans make a wrong move toward Iran, the shipment of energy will definitely face danger, and the Americans would not be able to protect energy supply in the region.”58

Iran has established a precedent for attacking oil shipments in the Gulf. During the Iran–Iraq war, each side targeted the other’s oil facilities, ports, and oil exports. Iran escalated attacks to include neutral Kuwaiti oil tankers and terminals and clandestinely laid mines in Persian Gulf shipping lanes while its ally Libya clandestinely laid mines in the Red Sea. The United States defeated Iran’s tactics by reflagging Kuwaiti oil tankers, clearing the mines, and escorting ships through the Persian Gulf, but a large number of commercial vessels were damaged during the “Tanker War” from 1984 to 1987.

Iran’s demonstrated willingness to disrupt oil traffic through the Persian Gulf in the past to place economic pressure on Iraq is a red flag to U.S. military planners. During the 1980s Tanker War, Iran’s ability to strike at Gulf shipping was limited by its aging and outdated weapons systems and the U.S. arms embargo imposed after the 1979 revolution. However, since the 1990s, Iran has been upgrading its military with new weapons from North Korea, China, and Russia, as well as with weapons manufactured domestically.

Today, Iran boasts an arsenal of Iranian-built missiles based on Russian and Chinese designs that pose significant threats to oil tankers as well as warships. Iran is well stocked with Chinese-designed anti-ship cruise missiles, including the older HY-2 Seersucker and the more modern CSS-N-4 Sardine and CSS-N-8 Saccade models. Iran also has reverse engineered Chinese missiles to produce its own anti-ship cruise missiles, the Ra’ad and Noor.59 Shore-based missiles deployed along Iran’s coast would be augmented by aircraft-delivered laser-guided bombs and missiles, as well as by television-guided bombs.

Iran has a large supply of anti-ship mines, including modern mines that are far superior to the simple World War I–style contact mines that Iran used in the 1980s. They include the Chinese-designed EM-52 “rocket” mine, which remains stationary on the sea floor and fires a homing rocket when a ship passes overhead. In addition, Iran can deploy mines or torpedoes from its three Kilo-class submarines, which would be effectively immune to detection for brief periods when running silent and remaining stationary on a shallow bottom just outside the Strait of Hormuz,60 and also could deploy mines by mini-submarines, helicopters, or small boats disguised as fishing vessels.

Iran’s Revolutionary Guard naval forces have developed swarming tactics using fast attack boats and also could deploy naval commandos trained to attack using small boats, mini-submarines, and even jet skis. The Revolutionary Guards also have underwater demolition teams that could attack offshore oil platforms and other facilities.

On April 28, 2015, the Revolutionary Guard naval force seized the Maersk Tigris, a container ship registered in the Marshall Islands, near the Strait of Hormuz. Tehran claimed that it seized the ship because of a previous court ruling ordering the Maersk Line, which charters the ship, to make a payment to settle a dispute with a private Iranian company. The ship was later released after being held for more than a week.61 An oil tanker flagged in Singapore, the Alpine Eternity, was surrounded and attacked by Revolutionary Guard gunboats in the strait on May 14, 2015, when it refused to be boarded. Iranian authorities alleged that it had damaged an Iranian oil platform in March, although the ship’s owners maintained that it had hit an uncharted submerged structure.62 The Revolutionary Guard’s aggressive tactics in using commercial disputes as pretexts for the illegal seizures of transiting vessels prompted the U.S. Navy to escort American and British-flagged ships through the Strait of Hormuz for several weeks in May before tensions eased.

The July 2015 nuclear agreement has not altered the confrontational tactics of the Revolutionary Guards in the gulf.63 IRGC naval forces challenged U.S. naval forces in a series of incidents in 2015 and 2016. IRGC missile boats launched rockets within 1,500 yards of the carrier Harry S. Truman near the Strait of Hormuz in late December 2015, flew drones over U.S. warships, and detained and humiliated 10 American sailors in a provocative January 12, 2016, incident. Despite the fact that the two U.S. Navy boats carrying the sailors had drifted inadvertently into Iranian territorial waters, the vessels had the right of innocent passage, and their crews should not have been subjected to being disarmed, forced onto their knees, filmed, and exploited in propaganda videos.

Finally, Tehran could use its extensive terrorist network in the region to sabotage oil pipelines and other infrastructure or to strike oil tankers in port or at sea.

Terrorists pose a potential threat to oil tankers and other ships. Al-Qaeda strategist Abu Mus’ab al-Suri identified four strategic choke points that should be targeted for disruption: the Strait of Hormuz, the Suez Canal, the Bab el-Mandeb Strait, and the Strait of Gibraltar.64 In 2002, al-Qaeda terrorists attacked and damaged the French oil tanker Limbourg off the coast of Yemen. Al-Qaeda also almost sank the USS Cole, a guided-missile destroyer, in the port of Aden, killing 17 American sailors with a suicide boat bomb in 2000. An Egyptian patrol boat was attacked in November 2014 by the crews of small boats suspected of smuggling arms to Islamist terrorists in Gaza. In July 2015, the Islamic State–Sinai Province claimed responsibility for a missile attack on an Egyptian coastguard vessel.

Terrorists also have targeted the Suez Canal. In two incidents on July 29 and August 31, 2013, ships in the waterway were attacked with rocket-propelled grenades. The attacks were claimed by a shadowy Islamist extremist group called the Furqan Brigades, which operated in Egypt’s Sinai Peninsula.65 The vessels reportedly escaped major damage. More important, the canal was not forced to close, which would have disrupted global shipping operations, ratcheted up oil prices, and complicated the deployment of U.S. and NATO naval vessels responding to potential crises in the Middle East, Persian Gulf, and Horn of Africa.

Over the past decade, piracy off the coast of Somalia has threatened shipping near the Bab el-Mandeb Strait and the Gulf of Aden. Recently, however, the frequency of pirate attacks in the region has dropped. In 2013, according to the U.S. Navy, hijackings of major shipments off the coast of Somalia plummeted to zero.66 By early 2015, it appeared that piracy off the coast of Somalia had abated, at least temporarily, due to security precautions such as the deployment of armed guards on board cargo ships.67 Pirate activity, however, continues to threaten international trade and the safety of the international commons, particularly off the coasts of West Africa and Southeast Asia. A resurgence in the waters around the Middle East cannot be discounted.

WWTA: The WWTA does not reference maritime threats in the Middle East region.

Summary: Iran poses the chief potential threat to shipping in the Strait of Hormuz, while various terrorist groups pose the chief threats to shipping in the Suez Canal and the Bab el-Mandeb Strait. Although pirate attacks off the coast of Somalia have declined steeply in recent years, the potential for their return remains.

Airspace. The Middle East is particularly vulnerable to attacks on civilian aircraft. Large quantities of arms, including man-portable air defense systems (MANPADS), were looted from Libyan arms depots after the fall of Muammar Qadhafi’s regime in 2011. Although Libya is estimated to have had up to 20,000 MANPADS, mostly old Soviet models, only about 10,000 have been accounted for, and an unknown number may have been smuggled out of Libya, which is a hotbed of Islamist radicalism.68

U.S. intelligence sources estimated that at least 800 MANPADS fell into the hands of foreign insurgent groups after being moved out of Libya.69 Libyan MANPADS have turned up in the hands of AQIM, the Nigerian Boko Haram terrorist group, and Hamas in Gaza. At some point, one or more could be used in a terrorist attack against a civilian airliner. Insurgents or terrorists also could use anti-aircraft missile systems captured from regime forces in Iraq and Syria. In January 2015, a commercial airliner landing at Baghdad International Airport was hit by gunfire that injured a passenger and prompted a temporary suspension of flights to Baghdad.

Al-Qaeda also has used MANPADS in several terrorist attacks. In 2002, it launched two SA-7 MANPADS in a failed attempt to bring down an Israeli civilian aircraft in Kenya. In 2007, the al-Qaeda affiliate al-Shabaab shot down a Belarusian cargo plane in Somalia, killing 11 people.70 Al-Qaeda’s al-Nusra Front and the Islamic State have acquired substantial numbers of MANPADS from government arms depots in Iraq and Syria. Although such weapons may pose only a limited threat to modern warplanes equipped with countermeasures, they pose a growing threat to civilian aircraft in the Middle East and could be smuggled into the United States and Europe to threaten aircraft there.

The Islamic State–Sinai Province claimed responsibility for a bomb that destroyed Metrojet Flight 9268, a Russian passenger jet en route from Sharm el-Sheikh, Egypt, to Saint Petersburg, Russia, on October 31, 2015. The incident claimed the lives of 224 people on the plane, one of the biggest death tolls in a terrorist attack in recent years. The May 19, 2016, crash of EgyptAir flight MS804, which killed 66 people flying from Paris, France, to Cairo, Egypt, has been attributed to a fire, but the cause of that onboard fire has not yet been determined.

WWTA: The WWTA makes no mention of the terrorist threat to airspace in the Middle East.

Summary: Al-Qaeda, the Islamic State, and other terrorists have seized substantial numbers of anti-aircraft missiles from military bases in Iraq, Libya, and Syria that pose potential threats to safe transit of airspace in the Middle East, North Africa, and elsewhere.

Space. Iran has launched satellites into orbit, but there is no evidence that it has an offensive space capability. Tehran successfully launched three satellites in February 2009, June 2011, and February 2012 using the Safir space launch vehicle, which uses a modified Ghadr-1 missile for its first stage and has a second stage that is based on an obsolete Soviet submarine-launched ballistic missile, the R-27.71 The technology probably was transferred by North Korea, which built its BM-25 missiles using the R-27 as a model.72 Safir technology could be used as a basis to develop long-range ballistic missiles.

Iran claimed to have launched a monkey into space and returned it safely to Earth twice in 2013.73 Tehran also announced in June 2013 that it had established its first space tracking center to monitor objects in “very remote space” and to help manage the “activities of satellites.”74

WWTA: The WWTA does not reference Iranian space capabilities.

Summary: Though Iran has launched satellites into orbit successfully, there is no evidence that it has developed an offensive space capability that could deny others the use of space or exploit space as a base for offensive weaponry.

Cyber Threats. Iranian cyber capabilities present a significant threat to the U.S. and its allies. Iran has developed offensive cyber capabilities as a tool of espionage and sabotage. Tehran claims to have the world’s fourth largest cyber force, “a broad network of quasi-official elements, as well as regime-aligned ‘hacktivists,’ who engage in cyber activities broadly consistent with the Islamic Republic’s interests and views.”75

The creation of the “Iranian Cyber Army” in 2009 marked the beginning of a cyber offensive against those whom the Iranian government regards as enemies. A hacking group dubbed the Ajax Security Team, believed to be operating out of Iran, has used malware-based attacks to target U.S. defense organizations and has successfully breached the Navy Marine Corps Intranet. In addition, the group has have targeted dissidents within Iran, seeding versions of anti-censorship tools with malware and gathering information about users of those programs.76 Iran has invested heavily in cyber capabilities, with an annual budget reported to be almost $1 billion in 2012.77

Hostile Iranian cyber activity has increased significantly since the beginning of 2014 and could threaten U.S. critical infrastructure, according to an April 2015 report released by the American Enterprise Institute. The Islamic Revolutionary Guard Corps and Sharif University of Technology are two Iranian institutions that investigators have linked to efforts to infiltrate U.S. computer networks, according to the report.78

Iran allegedly has used cyber weapons to engage in economic warfare, most notably the sophisticated and debilitating denial-of-service attacks against a number of U.S. financial institutions, including the Bank of America, JPMorgan Chase, and Citigroup.79 In February 2014, Iran launched a crippling cyber attack against the Sands Casino in Las Vegas, owned by Sheldon Adelson, a leading supporter of Israel who is known to be critical of the Iranian regime.80 In 2012, Tehran was suspected of launching the “Shamoon” virus attack on Saudi Aramco, the national oil company that produces approximately 10 percent of the world’s oil, which destroyed around 30,000 computers, as well as an attack on Qatari natural gas company Rasgas’s computer networks.81

U.S. officials warned of a surge of sophisticated computer espionage by Iran in the fall of 2015 that included a series of cyber attacks against State Department officials.82 In March 2016, the Justice Department indicted seven Iranian hackers for penetrating the computer system that controlled a dam in the State of New York.83

The sophistication of these and other Iranian cyber attacks, together with Iran’s willingness to use these weapons, has led various experts to name Iran as one of America’s most cyber-capable opponents. Iranian cyber forces have even gone so far as to create fake online personas in order to extract information from U.S. officials through accounts such as LinkedIn, YouTube, Facebook, and Twitter.84

WWTA: The 2015 WWTA assessed that “Iran very likely values its cyber program as one of many tools for carrying out asymmetric but proportional retaliation against political foes, as well as a sophisticated means of collecting intelligence.” In addition, “Iranian actors have been implicated in the 2012–13 DDOS attacks against US financial institutions and in the February 2014 cyber attack on the Las Vegas Sands casino company.”85

Summary: Iranian cyber capabilities present significant espionage and sabotage threats to the U.S. and its allies, and Tehran has shown willingness and skill in using them.

Threat Scores

Iran. Iran represents by far the most significant security challenge to the United States, its allies, and its interests in the greater Middle East. Its open hostility to the United States and Israel, sponsorship of terrorist groups like Hezbollah, and history of threatening the commons underscore the problem it could pose. Today, Iran’s provocations are mostly a concern for the region and America’s allies, friends, and assets there. Iran relies heavily on irregular (to include political) warfare against others in the region and fields more ballistic missiles than any of its neighbors. The development of its ballistic missiles and potential nuclear capability also mean that it poses a long-term threat to the security of the U.S. homeland.

According to the International Institute for Strategic Studies’ Military Balance 2016, among the key weapons in Iran’s inventory are 22-plus MRBMs, 18-plus SRBMs, 1,663 main battle tanks, 21 tactical submarines, seven corvettes, 13 amphibious landing ships, and 334 combat-capable aircraft. There are 523,000 personnel in the armed forces, including 350,000 in the Army, 125,000 in the Islamic Revolutionary Guard Corps, and 18,000 in the Navy. With regard to these capabilities, the IISS assesses that:

Iran continues to rely on a mix of ageing combat equipment, reasonably well-trained regular and Islamic Revolutionary Guard Corps (IRGC) forces, and its ballistic-missile inventory to underpin the security of the state. The IRGC, including senior military leaders, has been increasingly involved in the civil war in Syria, supporting President Bashar al-Assad’s regular and irregular forces; it was first deployed to Syria in an “advisory” role in 2012….

The military continues to struggle with an ageing inventory of primary combat equipment that ingenuity and asymmetric warfare techniques can only partially offset….

The nuclear agreement with the P5+1 and the European Union also begins to open the way for Iran to revamp its equipment inventory, with China and Russia potentially major suppliers, though sales of conventional systems remain embargoed for five years.86

This Index assesses the overall threat from Iran, considering the range of contingencies, as “aggressive” and “gathering.” Iran’s capability score has increased over the 2016 Index due to a combination of Tehran’s continued weapons developments and ability to develop its nuclear program.


Greater Middle East–Based Terrorism

Collectively, the varied non-state actors in the Middle East that are vocally and actively opposed to the United States are the closest to being rated “hostile” with regard to the degree of provocation they exhibit. These groups, from the Islamic State to al-Qaeda and its affiliates, Hezbollah, and the range of Palestinian terrorist organizations in the region, are primarily a threat to America’s allies, friends, and interests in the Middle East. Their impact on the American homeland is mostly a concern for American domestic security agencies. However, they pose a challenge to the stability of the region that could result in the emergence of more dangerous threats to the United States.

The IISS Military Balance addresses only the military capabilities of states. Consequently, it does not provide any accounting of such entities as Hezbollah, Hamas, al-Qaeda, or the Islamic State.

This Index assesses the overall threat from greater Middle East–based terrorism, considering the range of contingencies, as “hostile” and “capable.”87 Both of these scores represent a more threatening assessment by one level than the 2016 Index, indicating the breadth of advances made across the globe by ISIS and the terrorist group’s ability to spread its message and gain followers worldwide.


  1. James Phillips, “The Yemen Bombing: Another Wake-up Call in the Terrorist Shadow War,” Heritage Foundation Executive Memorandum No. 773, October 25, 2000, 

  2. Stephen F. Hayes and Thomas Joscelyn, “Connecting the Dots,” The Weekly Standard, November 23, 2009, (accessed September 17, 2014). 

  3. Peter Finn, “Al-Awlaki Directed Christmas ‘Underwear Bomber’ Plot, Justice Department Memo Says,” The Washington Post, February 10, 2012, (accessed September 17, 2014). 

  4. U.S. Department of State, Bureau of Counterterrorism, “Foreign Terrorist Organizations,” Chapter 6 in Country Reports on Terrorism 2015, June 2016, (accessed August 8, 2016). 

  5. Eric Schmitt, “Al Qaeda Turns to Syria, With a Plan to Challenge ISIS,” The New York Times, May 15, 2016, (accessed August 8, 2016). 

  6. Lisa Curtis, ed., “Combatting the ISIS Foreign Fighter Pipeline: A Global Approach,” Heritage Foundation Special Report No. 180, January 6, 2016, p. 3, (accessed August 8, 2016). 

  7. Eric Schmitt, “U.S. Says Its Strikes Are Hitting More Significant ISIS Targets,” The New York Times, May 25, 2016, (accessed August n8, 2016). 

  8. Curtis, ed., “Combatting the ISIS Foreign Fighter Pipeline,” p. 5. 

  9. Brian Bennett, “Al-Qaeda in Iraq Threatens Attacks in U.S.,” Los Angeles Times, July 25, 2012, (accessed September 17, 2014). 

  10. James Phillips and Cassandra Lucaccioni, “Al-Qaeda Recruits Americans in Syria,” The Daily Signal, January 10, 2014, (accessed September 17, 2014). 

  11. Schmitt, “Al Qaeda Turns to Syria.” 

  12. U.S. Department of State, Bureau of Counterterrorism, “Foreign Terrorist Organizations,” Chapter 6 in Country Reports on Terrorism 2012, May 2013, (accessed September 17, 2014). 

  13. Associated Press, “ISIL Says It Faces War with Nusra in Syria,” Al Jazeera, last updated March 8, 2014,
    (accessed September 17, 2014). 

  14. James Phillips, “The Rise of Al-Qaeda’s Khorasan Group: What It Means for U.S. National Security,” Heritage Foundation Issue Brief No. 4281, October 6, 2014, at: 

  15. Adam Goldman, Greg Miller, and Nicole Rodriquez, “American Who Killed Himself in Syria Suicide Attack Was from South Florida,” The Washington Post, May 31, 2014, (accessed September 17, 2014). 

  16. Adam Goldman, “Ohio Man Who Trained with Jabhat al-Nusra Is Indicted on Terrorism Charges,” The Washington Post, April 16, 2015, (accessed June 26, 2015). 

  17. Evan Perez and Tom LoBianco, “FBI Head: Khorasan Group Diminished; ISIS Bigger Threat than al Qaeda,” CNN, July 23, 2015, (accessed August 8, 2016). 

  18. Eric Schmitt and Ben Hubbard, “Suicide Bomber in Syria Was U.S. Citizen, Officials Say,” The New York Times, May 28, 2014,

    (accessed September 17, 2014). 

  19. Sari Horwitz, “Eric Holder Urges European Countries to Help Stop Flow of Radicals to Syria,” The Washington Post, July 8, 2014, (accessed September 17, 2014). 

  20. U.S. Department of State, Country Reports on Terrorism 2015. 

  21. William Maclean, “Local Wars Blur al-Qaeda’s Threat to West,” Reuters, July 5, 2012, (accessed September 17, 2014). 

  22. James R. Clapper, Director of National Intelligence, “Statement for the Record: Worldwide Threat Assessment of the US Intelligence Community, Senate Armed Services Committee,” February 9, 2016, p. 4, (accessed August 8, 2016). Cited hereafter as 2016 WWTA

  23. Rebecca Leung, “Hezbollah: ‘A-Team of Terrorists,’” CBS News, April 18, 2003, (accessed November 10, 2014). 

  24. Suzanne Kelly, “Experts: Hezbollah Positioned for Attack in U.S.,” CNN, March 21, 2012, (accessed September 17, 2014). 

  25. 2016 WWTA, p. 6. 

  26. National Air and Space Intelligence Center, “Ballistic and Cruise Missile Threat,” July 11, 2013, p. 3, (accessed September 17, 2014). 

  27. U.S. Department of Defense, unclassified “Annual Report on Military Power of Iran: Executive Summary,” January 2014, (accessed August 8, 2016). 

  28. 2016 WWTA, p. 8. 

  29. Saeed Ghasseminejad, “Iran Doubles Down on Its Military Budget,” Foundation for Defense of Democracies Policy Brief,
    June 3, 2016, (accessed August 8, 2016). 

  30. Reuters, “Iran Says Russia Delivers First Part of S-300 Defense System,” April 11, 2016, (accessed August 8, 2016). 

  31. Farzin Nadimi, “Iran and Russia’s Growing Defense Ties,” Washington Institute for Near East Policy, PolicyWatch No. 2563, February 18, 2016,
    (accessed August 8, 2016). 

  32. Sam Dagher and Asa Fitch, “Iran Expands Role in Syria in Conjunction with Russia’s Airstrikes,” The Wall Street Journal,
    October 2, 2015, (accessed August 8, 2016). 

  33. Nuclear Threat Initiative, Country Profiles, “Iran: Missile,” last updated July 2014, (accessed September 17, 2014). 

  34. Ibid. 

  35. Lieutenant General Michael T. Flynn, Director, Defense Intelligence Agency, “Annual Threat Assessment: Statement Before the Senate Armed Services Committee,” February 11, 2014, p. 20, (accessed September 17, 2014). 

  36. Tim Hume and Alireza Hajihosseini, “Iran Fires Ballistic Missiles a Day After Test; U.S. Officials Hint at Violation,” CNN,
    March 9, 2016, (accessed August 8, 2016). 

  37. See James Phillips, “Iran’s Nuclear Program: What Is Known and Unknown,” Heritage Foundation Backgrounder No. 2393,
    March 26, 2010, 

  38. Valerie Lincy and Gary Milhollin, “Iran’s Nuclear Timetable,” Wisconsin Project for Nuclear Arms Control, Iran Watch, June 17, 2015, (accessed September 17, 2014). 

  39. News release, “Statement by the President on Iran,” The White House, July 14, 2015, (accessed September 21, 2014). 

  40. Christopher M. Blanchard, “Saudi Arabia: Background and U.S. Relations,” Congressional Research Service Report for Members and Committees of Congress, April 22, 2016, p. 20, (accessed August 8, 2016). 

  41. Kenneth Katzman, “Iran, Gulf Security, and U.S. Policy,” Congressional Research Service Report for Members and Committees of Congress, March 30, 2016, p. 24, (accessed August 8, 2016). 

  42. 2016 WWTA, p. 24. 

  43. Ibid., p. 8. 

  44. Avi Issacharoff, “Israel Raises Hezbollah Rocket Estimate to 150,000,” The Times of Israel, November 12, 2015, (accessed August 8, 2016). 

  45. Israel Defense Forces, “Rocket Attacks on Israel from Gaza,” IDF Blog, (accessed September 17, 2014). 

  46. Matthew Levitt, “Hezbollah Finances: Funding the Party of God,” Washington Institute for Near East Policy, February 2005, p. 3,
    (accessed September 17, 2014). 

  47. James Phillips, “Hezbollah’s Terrorist Threat to the European Union,” testimony before the Subcommittee on Europe, Committee on Foreign Affairs, U.S. House of Representatives, June 20, 2007, 

  48. Matthew Levitt, “Inside Hezbollah’s European Plots,” Washington Institute for Near East Policy, July 20, 2015, (accessed September 22, 2015). 

  49. 2016 WWTA, p. 6. 

  50. “Address at the Lord Mayor’s Annual Defence and Security Lecture by the Director General of the Security Service, Jonathan Evans,” London, MI5 Security Service, June 25, 2012, (accessed September 17, 2014). 

  51. 2016 WWTA, p. 4. 

  52. James Phillips, “Zarqawi’s Amman Bombings: Jordan’s 9/11,” Heritage Foundation WebMemo No. 919, November 18, 2005, 

  53. 2016 WWTA, p. 25. 

  54. Middle East Media Research Institute, “Former IRGC General Close to Supreme Leader Khamenei: ‘Bahrain Is a Province of Iran That Should Be Annexed to [It],’” Special Dispatch No. 6358, March 23, 2016, (accessed August 8, 2016). 

  55. Maayan Groisman, “Iranian Commander Threatens to Make Bahrain’s Royal Family ‘Disappear’,” The Jerusalem Post, June 21, 2016, (accessed August 8, 2016). 

  56. 2016 WWTA, p. 24. 

  57. U.S. Department of Energy, Energy Information Administration, “World Oil Transit Chokepoints,” last updated November 10, 2014,
    (accessed August 8, 2016). 

  58. Thom Shanker, “Rice Dismisses Iranian Cleric’s Warning on Oil,” The New York Times, June 5, 2006, (accessed September 17, 2014). 

  59. Robert Hewson, “Iran Ready to Field Maritime Cruise Missile,” Jane’s Defence Weekly, February 24, 2004, p. 13. 

  60. Michael Knights, Troubled Waters: Future U.S. Security Assistance in the Persian Gulf (Washington: Washington Institute for Near East Policy, 2006), p. 71,
    (accessed August 8, 2016). 

  61. Asa Fitch, “Iranian Authorities Release Maersk Tigris,” The Wall Street Journal, May 7, 2015, (accessed June 26, 2015). 

  62. ASC Staff, “Iran Attack: Alpine Eternity Moved to Dubai Drydocks,” Arabian Supply, May 26, 2015, (accessed June 26, 2015). 

  63. James Phillips, “The Dangerous Regional Implications of the Iran Nuclear Agreement,” Heritage Foundation Backgrounder No. 3124, May 9, 2016, 

  64. Niklas Anziger, “Jihad at Sea—Al Qaeda’s Maritime Front in Yemen,” Center for International Maritime Security, February 25, 2014, (accessed September 17, 2014). 

  65. Steven Starr, “Attacks in the Suez: Security of the Canal at Risk?” Combating Terrorism Center at West Point, CTC Sentinel, Vol. 7, Issue 1 (January 15, 2014),
    (accessed August 8, 2016). 

  66. Noah Rayman, “Did 2013 Mark the End of Somali Piracy?” Time, January 6, 2014, (accessed September 17, 2014). 

  67. Thomas Bennett, “Maritime Security at a Crossroads,” The Maritime Executive, April 26, 2015, (accessed May 28, 2015). 

  68. Scott Stewart, “The Continuing Threat of Libyan Missiles,” Stratfor Global Intelligence, Security Weekly, May 3, 2012, (accessed September 17, 2014). 

  69. David Ignatius, “Libyan Missiles on the Loose,” The Washington Post, May 8, 2012, (accessed September 17, 2014). 

  70. Matt Schroeder, “New Information on Somali MANPADS,” Federation of American Scientists, July 27, 2007, (accessed September 17, 2014). 

  71. Nuclear Threat Initiative, “Iran: Missile,” p. 4. 

  72. Viola Gienger and Tony Capaccio, “Iran May Have Missiles from North Korea, Cables Posted by Wikileaks Show,” Bloomberg, November 29, 2010, (accessed September 17, 2014). 

  73. Lateef Mungin, “Iran Claims 2nd Launch of Monkey into Space and Back,” CNN, December 14, 2013, (accessed September 17, 2014). 

  74. Nasser Karimi, “Iran Says It Sets up Space Monitoring Center,” Associated Press, June 9, 2013, (accessed September 17, 2014). 

  75. Ilan Berman, “The Iranian Cyber Threat, Revisited,” Statement before the Subcommittee on Cybersecurity, Infrastructure Protection, and Security Technologies, Committee on Homeland Security, U.S. House of Representatives, March 20, 2013,
    (accessed September 17, 2014). 

  76. Nart Villeneuve, Ned Moran, Thoufique Haq, and Mike Scott, “Operation Saffron Rose 2013,” FireEye Special Report, 2014, (accessed September 17, 2014). 

  77. Siobhan Gorman and Julian E. Barnes, “Iran Blamed for Cyberattacks,” The Wall Street Journal, October 12, 2012,
    (accessed September 17, 2014). 

  78. Frederick W. Kagan and Tommy Stiansen, The Growing Cyberthreat from Iran: The Initial Report of Project Pistachio Harvest, American Enterprise Institute Critical Threats Project and Norse Corporation, April 17, 2015, (accessed May 28, 2015). 

  79. Berman, “The Iranian Cyber Threat, Revisited,” p. 3. 

  80. Anthony Capaccio, David Lerman, and Chris Strohm, “Iran Behind Cyber-Attack on Adelson’s Sands Corp., Clapper Says,” Bloomberg Business, February 26, 2015, (accessed June 26, 2015). 

  81. Christopher Bronk and Eneken Tikk-Ringas, “The Cyber Attack on Saudi Aramco,” International Institute for Strategic Studies, Survival: Global Politics and Strategy, Vol. 55, No. 2 (April/May 2013), pp. 81–96,–global-politics-and-strategy-april-may-2013-b2cc/55-2-08-bronk-and-tikk-ringas-e272 (accessed June 19, 2014); Saudi Aramco, “Our Company,” (accessed June 19, 2014). 

  82. David E. Sanger and Nicole Perlroth, “Iranian Hackers Attack State Dept. via Social Media Accounts,” The New York Times, November 24, 2015, (accessed August 8, 2016). 

  83. Ellen Nakashima and Matt Zapotosky, “U.S. Charges Iran-Linked Hackers with Targeting Banks, N.Y. Dam,” The Washington Post, March 24, 2016, (accessed August 8, 2016). 

  84. David E. Sanger, “Iran Hackers Dangle a Familiar Name to Fish for Data,” The New York Times, May 30, 2014,

    (accessed September 17, 2014). 

  85. James R. Clapper, Director of National Intelligence, “Statement for the Record: Worldwide Threat Assessment of the US Intelligence Community, Senate Armed Services Committee,” February 26, 2015, p. 3, (accessed August 8, 2016). 

  86. International Institute for Strategic Studies, The Military Balance 2016: The Annual Assessment of Global Military Capabilities and Defence Economics (London: Routledge, 2016), pp. 327–331. 

  87. This Index scores threat capability as it relates to the vital national interests of the U.S. and the role and utility of U.S. military forces. Terrorist groups clearly have the ability to conduct attacks using improvised explosives, firearms, and even hijacked airplanes. The bombing of the Boston Marathon in April 2013, an attempted car bomb attack in New York City’s Times Square in May 2010, and al-Qaeda’s attacks on September 11, 2001, are stark examples. Often, the U.S. has handled terrorism as a law enforcement and intelligence collection matter, especially within the United States and when it presents a threat to particular U.S. interests in other countries. Compared to the types of threats posed by states such as China or Russia, terrorism is a lesser sort of threat to the security and viability of the U.S. as a global power. This Index does not dismiss the deaths, injuries, and damage that terrorists can inflict on Americans at home and abroad; it places the threat posed by terrorism in context with substantial threats to the U.S. homeland, the potential for major regional conflict, and the potential to deny U.S. access to the global commons. With this in mind, terrorist groups seldom have the physical ability either to accomplish the extreme objectives they state or to present a physical threat that rises to a level that threatens U.S. vital security interests. Of course, terrorist organizations can commit acts of war on a continuing basis, as reflected in their conduct in the war against al-Qaeda and its associates in which the United States has been engaged for more than a decade.