Terrorist groups come in many forms but have one thing in common: the use of violence to achieve their political objectives, whether their cause is driven by religious, ethnic, or ideological motivations. In general, these non-state actors operate in a very local context, usually within a specific country or sub-region. Sometimes a terrorist group’s objectives extend beyond the internationally recognized borders of a state because their identity as a group transcends such legal or geographic boundaries.
Terrorist groups rarely pose a threat to the United States that rises to the threshold used by this Index: a substantial threat to the U.S. homeland; the ability to precipitate a war in a region of critical interest to the U.S.; or the ability to threaten the free movement of people, goods, or services through the global commons. Those that do meet these criteria are assessed in this section.
Terrorist Threats to the Homeland from the Middle East and North Africa
Radical Islamist terrorism in its various forms remains a global threat to the safety of U.S. citizens. Many terrorist groups operate in the Middle East, but those inspired by Islamist ideology also operate in Europe, Asia, and Africa.
The primary terrorist groups of concern to the U.S. homeland and to Americans abroad are the Islamic State of Iraq and al-Sham (ISIS) and al-Qaeda. Their threat is amplified when they can exploit areas with weak or nonexistent governance to plan, train, equip, and launch attacks.
Al-Qaeda and Its Affiliates. Al-Qaeda was founded in 1988 by foreign veterans from among those who flocked to Afghanistan to join the war against the Soviet occupation in the 1980s. With Osama bin Laden appointed emir, al-Qaeda was envisaged as a fighting force that could defend Sunnis across the world and expand the Islamist struggle into a global revolutionary campaign.1
After 9/11, al-Qaeda’s leadership fled Afghanistan. Much of the original cadre has now been killed or captured, including Osama bin Laden, and other key al-Qaeda leaders have been killed by targeted strikes in Afghanistan, Pakistan, Syria, Yemen, and Somalia. However, segments of al-Qaeda’s leadership, including its emir, Ayman al-Zawahiri, survived. Some al-Qaeda lieutenants are believed to remain in the Afghanistan–Pakistan (AfPak) region; others have taken refuge in Iran.2 Al-Qaeda’s central leadership therefore continues to pose a potential threat to the U.S. homeland.
Al-Qaeda also dispersed its fighters further afield, allowing for the development of regional affiliates that shared the long-term goals of al-Qaeda’s general command and largely remained loyal to it. These affiliates have engaged with some success in local conflict environments. In particular, the Arab Spring uprisings that began in 2011 enabled al-Qaeda to advance its revolutionary agenda, taking advantage of failed or failing states in Iraq, Libya, Mali, Syria, and Yemen. It is through these affiliates that al-Qaeda is able to project regional strength most effectively.
Yemen. Yemen has long been a bastion of support for militant Islamism. Yemenis made up a disproportionate number of the estimated 25,000 foreign Muslims in the Afghan jihad against the Soviet Union in the 1980s. After that conflict ended, Yemen also attracted Westerners into the country to carry out terrorist operations there. In 1998, several British citizens were jailed for planning to bomb Western targets, including hotels and a church.3
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. 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.4 The first U.S. drone strike outside Afghanistan after 9/11 also took place in Yemen, targeting those connected to the attack on the Cole.5
After 9/11, and following crackdowns in other countries, Yemen became increasingly important as a base of operations for al-Qaeda. In September 2008, it launched an 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). This affiliate quickly emerged as one of the leading terrorist threats to the U.S.
Much of this threat initially centered on AQAP’s Anwar al-Awlaki, a charismatic American-born Yemeni cleric who directed several terrorist attacks on U.S. targets before being killed in a drone air strike in September 2011. He had an operational role in the plot executed by Umar Farouk Abdulmutallab, the failed suicide bomber who sought to destroy an airliner bound for Detroit on Christmas Day 2009.6 Awlaki was also tied to plots to poison food and water supplies, as well as to launch ricin and cyanide attacks,7 and is suspected of playing a role in the November 2010 plot to dispatch parcel bombs to the U.S. in cargo planes. Additionally, Awlaki was in contact with Major Nidal Hassan, who perpetrated the 2009 Fort Hood shootings that killed 13 soldiers.8
Since Awlaki’s death, the number of AQAP-sanctioned external operations in the West has diminished.9 However, his videos on the Internet have continued to radicalize and recruit young Muslims, including the perpetrators of the April 2013 bombing of the Boston Marathon that killed three people.10
AQAP’s threat to Western security, while seemingly slightly reduced by Awlaki’s death, is still pronounced. Another attempt to carry out a bombing of Western aviation using explosives concealed in an operative’s underwear was thwarted by a U.S.–Saudi intelligence operation in May 2012.11 In August 2013, U.S. interception of al-Qaeda communications led to the closure of 19 U.S. embassies and consulates across the Middle East and Africa because of fears that AQAP was planning a massive attack.12 In January 2015, two AQAP-trained terrorists murdered staff members and nearby police at Charlie Hebdo magazine in Paris.13 Then, in 2017, aviation was targeted once again by a plan to conceal bombs in laptop batteries.14
Much of AQAP’s recent activity has focused on exploiting the chaos of the Arab Spring in Yemen. AQAP acquired a significant amount of territory in 2011 and established governance in the country’s South, finally relinquishing this territory only after a Yemeni military offensive in the summer of 2012.15
AQAP further intensified its domestic activities after the overthrow of Yemen’s government by Iran-backed Houthi rebels in 2015, seizing the city of al-Mukalla and expanding its control of rural areas in southern Yemen. AQAP withdrew from al-Mukalla and other parts of the South in the spring of 2016, reportedly after the U.S.-backed Saudi–United Arab Emirates coalition had cut deals with AQAP, paying it to leave certain territory and even integrating some of its fighters into its own forces targeting the Houthis.16
More substantive progress has been achieved in the targeting of AQAP’s leadership. Said al-Shehri, a top AQAP operative, was killed in a drone strike in 2013. The group’s leader at the time, Nasir al-Wuhayshi, was killed in a drone strike in June 2015. Perhaps most significantly, Ibrahim al-Asiri, AQAP’s most notorious bomb maker, was killed in a U.S. strike in 2017. Since then, the tempo of U.S. drone strikes against AQAP has slowed.17
Despite U.S. drone activity, it is estimated that AQAP still has between 6,000 and 7,000 fighters.18 It therefore remains a potent force that could capitalize on the anarchy of Yemen’s multi-sided civil war to seize new territory and plan more attacks on the West.
Syria. Al-Qaeda’s Syrian affiliate, the al-Nusra Front (ANF), was established as an offshoot of the Islamic State of Iraq (ISI), al-Qaeda’s Iraq affiliate, in late 2011 by Abu Muhammad al-Julani, a lieutenant of ISI leader Abu Bakr al-Baghdadi.19 ANF had an estimated 5,000 to 10,000 members and emerged as one of the top rebel groups fighting the Assad dictatorship in Syria.20
ANF had some success in attracting Americans to its cause. An American Muslim recruited by ANF, Moner Mohammad Abusalha, conducted a suicide truck bombing in northern Syria on May 25, 2014, in the first reported suicide attack by an American in that country.21 At least five men have been arrested inside the U.S. for providing material assistance to ANF, including Abdirahman Sheik Mohamud, a naturalized U.S. citizen who was arrested in April 2015 after returning from training in Syria and was planning to launch a terrorist attack on U.S. soldiers based in Texas.22
In recent years, the al-Qaeda movement in Syria has undergone several name changes, allying itself with various Islamist rebel groups. This has made the degree of direct threat posed outside of Syria’s borders harder to assess.
In a May 2015 interview, al-Julani stated that al-Nusra’s intentions were purely local and that, “so as not to muddy the current war” in Syria, ANF was not planning to target the West.23 Then, in July 2016, al-Nusra rebranded itself as Jabhat Fath Al Sham (JFS), and al-Julani stated that it would have “no affiliation to any external entity,” a move that some regarded as a break from al-Qaeda and others regarded as a move to obscure its ties to al-Qaeda and reduce U.S. military pressure on the group.24
In January 2017, JFS merged as part of an alliance with other Islamist extremist movements into a new anti-Assad coalition: Hayat Tahrir al-Sham (HTS, Organization for the Liberation of the Levant). It was estimated that HTS had 12,000 to 14,000 fighters in March 2017.25 Further complicating matters surrounding al-Qaeda’s presence, another group in Syria connected to al-Qaeda, Hurras al-Din (Guardians of the Religion), was formed in March 2018.26 Among its ranks were those who defected from HTS, and its suspected emir is an Ayman al-Zawahiri acolyte.27
HTS 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 ISIS. However, the leadership of Abu Muhammad al-Julani and his tactical approach to the conflict, as well as the clear divisions within the Syrian jihad, have led to rebukes from Ayman al-Zawahiri and those loyal to him.28 Zawahiri has stressed the need for unity while lambasting the jihadist movement in Syria and its emphasis on holding territory in northwest Syria at the expense of intensifying the struggle against Assad.29
One entity that did pose a direct threat to the West was the Khorasan group, which was thought to comprise dozens of veterans of al-Qaeda’s operations in Afghanistan and Pakistan.30 Al-Zawahiri had dispatched this cadre of operatives to Syria, where they were embedded with ANF and—despite al-Julani’s statement that ANF was not targeting the West—charged with organizing terrorist attacks against Western targets. However, a series of U.S. air strikes in 2014–2015 degraded Khorasan’s capacity to organize terrorist attacks.
Al-Qaeda’s presence and activities in Syria, as well as the intent of those once aligned with it, are sometimes opaque, most likely on purpose. Even if offshoots of al-Qaeda are not currently emphasizing their hostility to the U.S., however, that will likely change if they succeed in further consolidating power in Syria.
The Sahel. Al-Qaeda in the Islamic Maghreb (AQIM) “has an estimated 1,000 fighters operating in the Sahel, including Algeria, northern Mali, southwest Libya, and Nigeria,” and “is based in southern and eastern Algeria (including isolated parts of the Kabylie region), Burkina Faso, Cote D’Ivoire, Libya, northern Mali, Niger, and Tunisia.”31
AQIM’s roots lie in the Algerian civil war of the 1990s, when the Algerian government cancelled the second round of elections following the victory of the Islamic Salvation Front (FIS) in the first round. The armed wing of the FIS, the Armed Islamic Group (GIA), responded by launching a series of attacks, executing those even suspected of working with the state. The group also attempted to implement sharia law in Algeria.
The GIA rapidly alienated regular Algerians, and by the late 1990s, an offshoot, the Salafist Group for Preaching and Combat (GSPC), emerged. Its violence, somewhat less indiscriminate than the GIA’s, was focused on security and military targets. Having failed to overthrow the Algerian state, the GSPC began to align itself with al-Qaeda, and Ayman al-Zawahiri announced its integration into the al-Qaeda network in a September 2006 video. The GSPC subsequently took the AQIM name.
AQIM has carried out a series of regional attacks and has focused on kidnapping Westerners. Some of these hostages have been killed,32 but more have been used to extort ransoms from Western governments.33 Like other al-Qaeda affiliates, AQIM also took advantage of the power vacuums that emerged from the Arab Spring, particularly in Libya where Islamist militias flourished. The weak central government was unable to tame fractious militias, curb tribal and political clashes, or dampen rising tensions between Arabs and Berbers in the West and Arabs and the Toubou tribe in the South.
The September 11, 2012, attack on the U.S. diplomatic mission in Benghazi underscored the extent to which Islamist extremism had flourished in the region. The radical Islamist group that launched the attack, Ansar al-Sharia, had links to AQIM and shared its violent ideology. AQIM and likeminded Islamist allies also grabbed significant amounts of territory in northern Mali in late 2012, implementing a brutal version of sharia law, until a French military intervention helped to push them back.
AQIM continues to support and works alongside various jihadist groups in the region. In March 2017, the Sahara branch of AQIM merged with three other al-Qaeda or al-Qaeda–linked organizations based in the Sahel to form the Group for Support of Islam and Muslims (JNIM), an organization that has pledged allegiance to al-Qaeda emir Ayman al-Zawahiri.34
AQIM is not known to have explicitly targeted the U.S. homeland in recent years, 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.
The Islamic State of Iraq and al-Sham and Its Affiliates. The Islamic State of Iraq and al-Sham (ISIS) is an al-Qaeda splinter group that has outstripped its parent organization in terms of its immediate threats to U.S. national interests.
The Islamic State of Iraq (ISI), the precursor to ISIS and an al-Qaeda offshoot, was perceived by some Western policymakers as having been strategically defeated following the U.S. “surge” of 2006–2007 in Iraq. However, the group benefited from America’s effectively having withdrawn—both politically and militarily—from Iraq in the 2010–2011 period, as well as from the chaos in Syria where Bashar al-Assad responded to the Arab Spring protests with bloody persecution.
In both Iraq and Syria, ISI had space in which to operate and a large disaffected pool of individuals from which to recruit. In April 2013, ISI emir Abu Bakr al-Baghdadi declared that the al-Nusra Front, the al-Qaeda affiliate operating in Syria, was merely a front for his operation and that a new organization was being formed: the Islamic State of Iraq and al-Sham (ISIS).
ISIS sought to establish an Islamic state governed by its interpretation of sharia law, posing an existential threat to Christians, Shiite Muslims, Yazidis, and other religious minorities. Its long-term goals continue to be a jihad to drive Western influence out of the Middle East; diminish and discredit Shia Islam, which it considers apostasy; and become the nucleus of a global Sunni Islamic empire.
With both al-Qaeda leader Ayman al-Zawahiri and ANF emir Abu Mohammed al-Julani unsuccessful in reining in al-Baghdadi, ISIS was expelled from the al-Qaeda network in February 2014. Despite this, ISIS swept through parts of northern and western Iraq and in June 2014 declared the return of the Caliphate, with its capital in the northern Syrian city of Raqqa. It subsequently kidnapped and then murdered Westerners working in Syria, including American citizens.
A U.S.-led international coalition was assembled to chip away at ISIS’s control of territory. The Iraqi Army and Iranian-backed militias broke its control of Mosul in July 2017, and the U.S.-backed Syrian Democratic Forces militia liberated Raqqa in October 2017, with ISIS’s last town (Baghouz) falling in March 2019. ISIS fighters have retreated, have adopted insurgent tactics, and will continue to pose a regional terrorist threat with direct implications for the U.S. In January 2019, for example, U.S. troops were killed in a suicide bombing at a market in Manbij in northern Syria.35
Although ISIS’s territorial control has now been broken in Iraq and Syria, its presence has spread far beyond that territory. Terrorist groups around the world have pledged allegiance to Abu Bakr al-Baghdadi, and ISIS now has affiliates in the Middle East, in South and Southeast Asia, and throughout Africa.
ISIS poses a threat to stability in all of these regions, seeking to overthrow their governments and impose Islamic law. In pursuit of this cause, ISIS has shown itself willing to kill Christians and other non-Muslims while committing attacks on the police and soldiers. An Islamic State in the Greater Sahara ambush in Niger in October 2017, for example, resulted in the death of four U.S. special operations troops.36 In addition, ISIS has made threats against government embassies, including those of the U.S., in its areas of influence.37
ISIS poses an ongoing threat to life in the West. In the U.S., on May 3, 2015, two extremists in contact with an ISIS operative in Syria were fatally shot by police before they could commit mass murder in Garland, Texas.38
More commonly, however, the ISIS ideology has inspired individuals and small groups to plan attacks in the U.S. Tashfeen Malik, one of the perpetrators of the December 2, 2015, shootings that killed 14 people in San Bernardino, California, pledged allegiance to al-Baghdadi.39 ISIS then claimed responsibility for the June 12, 2016, shootings at a nightclub in Orlando, Florida, that killed 49 people. Omar Mateen, the perpetrator, had pledged allegiance to al-Baghdadi, although there is no evidence to show that the attacks were directed by ISIS.40 The group also claimed responsibility for the October 31, 2017, vehicular attack by Sayfullo Saipov in New York that killed eight.41 Saipov, too, had pledged allegiance to ISIS’s emir but did not appear to be operationally guided by ISIS.42 Such terrorist attacks, incited but not directed by ISIS, are likely to continue for the foreseeable future.
ISIS has also attempted complex attacks on aviation. It claimed responsibility for the October 31, 2015, downing of a Russian passenger jet over Egypt’s Sinai Peninsula that killed 224 people and also tried to bring down a flight heading from Sydney to Abu Dhabi by concealing an explosive device inside a meat grinder.43
ISIS had well-publicized success in attracting the support of foreign fighters. Approximately 250 from the U.S. traveled or attempted to travel to Syria.44 There is the potential for an ongoing threat from these individuals, who are likely to have received military training, upon return to the U.S. either in terms of attack planning or in recruiting future generations of jihadists.
ISIS had greater success attracting those from Europe, with approximately 6,000 departing from European countries.45 The foreign fighter threat in that continent has led to several attacks. Mehdi Nemmouche, a French citizen of Algerian origin who shot and killed four civilians at the Jewish Museum in Brussels in May 2014, for example, was an ISIS-aligned terrorist who had fought in Syria.46 In August 2015, Ayoub el-Khazzani, a Moroccan, attempted to gun down passengers in a train travelling between Amsterdam and Paris. Passengers, including two members of the U.S. Army, restrained him.47
Similarly, a group of ISIS foreign fighters teamed with local Islamist terrorists to launch a series of suicide and gun attacks on a music venue, restaurants, cafes, and a football stadium, killing 130 and injuring 368 people in Paris, France, in November 2015.48 Recruits from within the same network then killed 32 people and injured around 300 more in shootings and suicide bombings across Brussels, Belgium, in March 2016.49
ISIS ideology has also inspired a wave of attacks in Europe, including one carried out by a Tunisian who used a truck to kill 86 people and injure 434 more at a Bastille Day celebration in Nice, France, in July 2016.50 In another such attack, in June 2017, three men killed eight people and injured 47 on or near London Bridge in London, England, by running over them or stabbing them.51
ISIS has demonstrated an interest in carrying out biological attacks. Sief Allah H., a Tunisian asylum seeker who was in contact with ISIS, and his German wife Yasmin H. were arrested in Cologne in June 2018 after they successfully produced ricin as part of a suspected attack.52 This was the first time that ricin was successfully produced in the West as part of an alleged Islamist plot.
Overall, as of May 2019, ISIS had had some involvement—ranging from merely inspirational to hands-on and operational—in over 150 plots and attacks in Europe since January 2014 that had led to 371 deaths and over 1,700 injuries.53 This includes the loss of American lives abroad. An American college student was killed in Paris in November 2015, four Americans were killed in the Brussels attack of March 2016, and another three were killed in the Nice attack of July 2016.54 Moreover, the threat is by no means confined to Europe: Americans were also killed in ISIS-claimed attacks in Tajikistan in July 2018 and Sri Lanka in April 2019.55
ISIS has lost its Caliphate, but it remains a highly dangerous adversary capable of planning and executing attacks regionally and—at the very least—inspiring them in the West. It appears to be transitioning from a quasi-state to an insurgency, relying on its affiliates to project strength far beyond its former Syrian and Iraqi strongholds.
Meanwhile, despite sustained losses to its leadership, al-Qaeda remains resilient. It has curried favor with other Sunnis in particular areas of strategic importance to it, has focused its resources on local conflicts, has occasionally controlled territory, and has de-emphasized (but not eschewed) focus on the global jihad. This approach has been particularly noticeable since the Arab Spring.
Regardless of any short-term tactical considerations, both groups ultimately aspire to attack the U.S. at home and U.S. interests abroad. While the U.S. has hardened its domestic defenses, making this a tricky prospect for both groups, they can rely on radicalized individuals living within the U.S. to take up the slack. Furthermore, as has been demonstrated time and again, there are ample opportunities to target Americans based in countries that are more vulnerable to terrorist attack.
If it wishes to contain and ultimately end Islamist violence, the U.S. must continue to bring effective pressure to bear on these groups and those that support them. This Index assesses the threat from ISIS, al-Qaeda, and their affiliated organizations as “capable” and “aggressive.”
- Peter L. Bergen, The Osama bin Laden I Know: An Oral History of al Qaeda’s Leader (New York: Free Press, 2006), pp. 82–83.
- See, for example, United Nations Security Council, Twenty-Second Report of the Analytical Support and Sanctions Monitoring Team Submitted Pursuant to Resolution 2368 (2017) Concerning ISIL (Da’esh), Al-Qaida and Associated Individuals and Entities, S/2018/705, July 27, 2018, pp. 15 and 18, https://www.un.org/en/ga/search/view_doc.asp?symbol=S/2018/705&referer=/english/&Lang=E (accessed July 9, 2019).
- BBC News, “Britons Convicted of Yemen Bomb Plot,” August 9, 1999, http://news.bbc.co.uk/2/hi/middle_east/415096.stm (accessed July 9, 2019).
- James Phillips, “The Yemen Bombing: Another Wake-up Call in the Terrorist Shadow War,” Heritage Foundation Executive Memorandum No. 773, October 25, 2000, http://www.heritage.org/middle-east/report/the-yemen-bombing-another-wake-call-the-terrorist-shadow-war.
- CNN, “Sources: U.S. Kills Cole Suspect,” November 5, 2002, http://www.cnn.com/2002/WORLD/meast/11/04/yemen.blast/index.html (accessed July 9, 2019).
- Jeremy Pelofsky, “Prosecutors Say al Qaeda Leader Awlaki Directed Underwear Bomber,” Reuters, February 10, 2012, https://www.reuters.com/article/us-usa-security-abdulmutallab/prosecutors-say-al-qaeda-leader-awlaki-directed-underwear-bomber-idUSTRE8191VL20120210 (accessed July 9, 2019).
- Daniel Klaidman, Kill or Capture: The War on Terror and the Soul of the Obama Presidency (New York: Houghton Mifflin Harcourt, 2012), p. 216.
- Mark Schone and Rehab el-Buri, “Fort Hood: Hasan Asked Awlaki If It Was Okay to Kill American Soldiers,” ABC News, December 23, 2009, https://abcnews.go.com/Blotter/FtHoodInvestigation/fort-hood-hasan-asked-awlaki-kill-american-soldiers/story?id=9410718 (accessed July 9, 2019).
- For more on the potential decline of AQAP’s external operations program, see Gregory D. Johnsen, “The Two Faces of Al-Qaeda in the Arabian Peninsula,” War on the Rocks, October 11, 2018, https://warontherocks.com/2018/10/the-two-faces-of-al-qaeda-in-the-arabian-peninsula/ (accessed July 9, 2019).
- Scott Shane, “The Enduring Influence of Anwar al-Awlaki in the Age of the Islamic State,” Combating Terrorism Center at West Point, CTC Sentinel, Vol. 9, Issue 7 (July 2016), pp. 15–19, https://ctc.usma.edu/app/uploads/2016/08/CTC-SENTINEL_Vol9Iss710.pdf (accessed July 9, 2019).
- BBC News, “Al-Qaeda Yemen Plane Bomb Plot Foiled by ‘Insider,’” May 8, 2012, https://www.bbc.com/news/world-us-canada-17994493 (accessed July 9, 2019).
- CBS News, “Yemen Terror Threat Prompts State Department to Evacuate Some Embassy Staff, Warn Americans to Leave Country ‘Immediately,’” August 6, 2013, https://www.cbsnews.com/news/yemen-terror-threat-prompts-state-department-to-evacuate-some-embassy-staff-warn-americans-to-leave-country-immediately/ (accessed July 9, 2019).
- Thomas Joscelyn, “Al Qaeda in the Arabian Peninsula Claims Responsibility for Charlie Hebdo Attack,” Foundation for Defense of Democracies Long War Journal, January 14, 2015, https://www.longwarjournal.org/archives/2015/01/al_qaeda_in_the_arab_2.php (accessed July 9, 2019).
- Barbara Starr and Rene Marsh, “AQAP Trying to Hide Explosives in Laptop Batteries, Official Says,” CNN, updated March 22, 2017, https://www.cnn.com/2017/03/21/politics/electronics-ban-devices-explosives-intelligence/index.html (accessed July 9, 2019).
- Robin Simcox, “Ansar al-Sharia and Governance in Southern Yemen,” Current Trends in Islamist Ideology, Vol. 14 (January 2013), pp. 58–72, https://www.hudson.org/research/9779-ansar-al-sharia-and-governance-in-southern-yemen (accessed July 9, 2019).
- Maggie Michael, Trish Wilson, and Lee Keath, “AP Investigation: US Allies, al-Qaida Battle Rebels in Yemen,” Associated Press, August 7, 2018, https://apnews.com/f38788a561d74ca78c77cb43612d50da (accessed July 9, 2019).
- Bill Roggio, “US Targets AQAP 8 Times in Past 3 Months,” Foundation for Defense of Democracies Long War Journal, April 2, 2019, https://www.longwarjournal.org/archives/2019/04/us-targets-aqap-8-times-in-past-3-months.php (accessed July 9, 2019).
- United Nations Security Council, Twenty-Second Report of the Analytical Support and Sanctions Monitoring Team, p. 9.
- Chapter 5, “Foreign Terrorist Organizations,” in U.S. Department of State, Bureau of Counterterrorism, Country Reports on Terrorism 2017, September 2018, pp. 320–321, https://www.state.gov/wp-content/uploads/2019/04/crt_2017.pdf (accessed July 9, 2019).
- Eric Schmitt, “Al Qaeda Turns to Syria, with a Plan to Challenge ISIS,” The New York Times, May 15, 2016, http://www.nytimes.com/2016/05/16/world/middleeast/al-qaeda-turns-to-syria-with-a-plan-to-challenge-isis.html?_r=0 (accessed July 9, 2019).
- Adam Goldman, Greg Miller, and Nicole Rodriguez, “American Who Killed Himself in Syria Suicide Attack Was from South Florida,” The Washington Post, May 31, 2014, http://www.washingtonpost.com/world/national-security/american-who-killed-himself-in-syria-suicide-attack-was-from-south-florida-official-says/2014/05/30/03869b6e-e7f4-11e3-a86b-362fd5443d19_story.html (accessed July 9, 2019).
- Adam Goldman, “Ohio Man Who Trained with Jabhat al-Nusra Is Indicted on Terrorism Charges,” The Washington Post, April 16, 2015, http://www.washingtonpost.com/world/national-security/ohio-man-who-trained-with-jabhat-al-nusra-is-indicted-on-terrorism-charges/2015/04/16/8e8ded08-e455-11e4-b510-962fcfabc310_story.html (accessed July 9, 2019).
- Agence France-Presse, “Chief of Al-Qaeda’s Syria Affiliate Pledges No Attacks on the West,” May 27, 2015, https://www.yahoo.com/news/chief-al-qaedas-syria-affiliate-pledges-no-attacks-221912033.html?ref=gs (accessed July 9, 2019).
- Thomas Joscelyn, “Analysis: Al Nusrah Front Rebrands Itself as Jabhat Fath Al Sham,” Foundation for Defense of Democracies Long War Journal, July 28, 2016, https://www.longwarjournal.org/archives/2016/07/analysis-al-nusrah-front-rebrands-itself-as-jabhat-fath-al-sham.php (accessed July 9, 2019).
- Charles Lister, “Al Qaeda Is Starting to Swallow the Syrian Opposition,” Foreign Policy, March 15, 2017, http://foreignpolicy.com/2017/03/15/al-qaeda-is-swallowing-the-syrian-opposition/ (accessed July 9, 2019).
- Thomas Joscelyn, “Jihadists Form ‘Guardians of the Religion’ Organization in Syria,” Foundation for Defense of Democracies Long War Journal, March 4, 2018, https://www.longwarjournal.org/archives/2018/03/jihadists-form-guardians-of-the-religion-organization-in-syria.php (accessed July 9, 2019).
- Thomas Joscelyn, “2 al Qaeda Leaders Reject Proposed Military Council in Syria,” Foundation for Defense of Democracies Long War Journal, January 30, 2019, https://www.longwarjournal.org/archives/2019/01/2-al-qaeda-leaders-reject-proposed-military-council-in-syria.php (accessed July 9, 2019).
- Thomas Joscelyn, “Analysis: Ayman al Zawahiri Calls for ‘Unity’ in Syria Amid Leadership Crisis,” Foundation for Defense of Democracies Long War Journal, December 2, 2017, https://www.longwarjournal.org/archives/2017/12/analysis-ayman-al-zawahiri-calls-for-unity-in-syria-amid-leadership-crisis.php (accessed July 9, 2019).
- Thomas Joscelyn, “Zawahiri Criticizes Jihadists in Syria for Clinging to Territory Under Turkey’s Protection,” Foundation for Defense of Democracies Long War Journal, February 7, 2019, https://www.longwarjournal.org/archives/2019/02/zawahiri-criticizes-jihadists-in-syria-for-clinging-to-territory-under-turkeys-protection.php (accessed July 9, 2019).
- 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, http://www.heritage.org/middle-east/report/the-rise-al-qaedas-khorasan-group-what-it-means-us-national-security.
- U.S. Department of State, Bureau of Counterterrorism, Country Reports on Terrorism 2017, p. 330.
- Raissa Kasolowsky and Kate Kelland, “Al Qaeda Kills British Hostage in Mali,” Reuters, June 3, 2009, https://www.reuters.com/article/us-qaeda-hostage/al-qaeda-kills-british-hostage-in-mali-idUSTRE5521HO20090603 (accessed July 9, 2019).
- U.S. Department of State, Bureau of Counterterrorism, Country Reports on Terrorism 2017, p. 329.
- Thomas Joscelyn, “Analysis: Al Qaeda Groups Reorganize in West Africa,” Foundation for Defense of Democracies Long War Journal, March 13, 2017, https://www.longwarjournal.org/archives/2017/03/analysis-al-qaeda-groups-reorganize-in-west-africa.php (accessed July 9, 2019).
- BBC News, “Syria War: ‘IS Suicide Bomber’ Kills US Troops in Manbij,” January 16, 2019, https://www.bbc.com/news/world-middle-east-46892118 (accessed July 9, 2019).
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