67 Islamist Terrorist Plots Since 9/11: Spike in Plots Inspired by Terrorist Groups, Unrest in Middle East

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67 Islamist Terrorist Plots Since 9/11: Spike in Plots Inspired by Terrorist Groups, Unrest in Middle East

April 22, 2015 5 min read Download Report

Authors: David Inserra and James Phillips

In late February, Abdirahman Sheik Mohamud, a naturalized U.S. citizen born in Somalia, was arrested in Ohio and charged with various terrorist activities. Last week, news came that a Federal Grand Jury had indicted Mohamud on additional federal charges, including providing material support to terrorists and making a false statement involving international terrorism. With the indictment came greater details of Mohamud’s travel to Syria, where he was trained by a terrorist group, and his return to the U.S. to target American soldiers in a terrorist attack.

This plot brings the total number of Islamist terrorist plots and attacks against the U.S. homeland since 9/11 to 67, with this indictment coming on the heels of three other plots that were foiled within 17 days of each other.[1] With terrorist plots spiking in the U.S., Congress must work to ensure that U.S. law enforcement and intelligence agencies have the tools they need to stop these terrorist plots. It is believed that Mohamud is the first American to have been trained by Syria-based terrorist groups to return to the U.S. in order to engage in terrorism. He is likely to be followed by others if current trends persist.

An International Terrorist Plot

Mohamud’s family came to the U.S. from Somalia when he was young and he became a naturalized citizen in February 2014. According to the indictment, Mohamud applied for a U.S. passport about one week later in order to join his brother Aden, who was fighting with the Nusra Front, the al-Qaeda franchise operating out of Syria. Prior to his travel to Syria, Mohamud communicated with an unnamed person about his plans and eagerness to join Aden, and his own willingness to kill any U.S. allies in battle. Mohamud discussed with this unnamed person which terrorist group would be best to join and how Mohamud could smuggle money to Aden.[2]

In April 2014, Mohamud purchased a one-way ticket to Athens. During a connecting stop in Istanbul, he left the airport and began communicating with Aden about where he was staying and how he could travel to Syria. Through a contact of Aden’s, Mohamud was picked up and smuggled into Syria. The indictment seems to indicate, though, that Mohamud intended to join ISIS not the Nusra Front, since he did not seem to meet up with his brother, and he subsequently posted photos on his Facebook page that appeared to have ISIS logos. Aden was killed sometime in May or early June 2014.[3]

After being trained in hand-to-hand combat, small arms, and explosives, Mohamud told an unnamed person that an ISIS cleric told him that he should return to the U.S. to commit terrorist acts. Mohamud told this unnamed person that he wanted to kill Americans, especially military personnel, police officers, or others in uniform, such as prison guards, and that he would soon join Aden. Upon returning to the U.S., Mohamud talked with a second unnamed person about his training and time in Syria. He also “talked about doing something big in the United States. He wanted to go to a military base in Texas and kill three or four American soldiers execution style.”[4] The second unnamed person believed that Mohamud was trying to recruit him for this plot.[5]

Implications of the Plot

This plot is the fifth Islamist terrorist plot foiled inside the United States in 2015 and, like most of the plots this year, targeted military personnel and facilities. Since 9/11, 19 attacks or plots have targeted the U.S. military on U.S. soil, making the military the most common target for Islamist terrorists. This plot is also the 56th homegrown plot, since Mohamud was radicalized here in the United States. Mohamud is also the first terrorist since 2010 to have trained in a terrorist training camp and then targeted the U.S. homeland. Perhaps most worrying, Mohamud appears to be the first terrorist to have emerged from the conflict in Syria with orders from his superiors to attack targets inside the U.S.[6]

More than 150 American passport holders have traveled to Syria, or attempted to travel there, to join the fighting, along with more than 20,000 fighters from more than 90 countries.[7] Many of those with American passports are believed to have joined ISIS or the Nusra Front. Some, like Mohamud’s brother Aden, have died in the fighting, but most of the rest are expected to return to the U.S. in the future, where they pose a potential terrorist threat.

Both the Nusra Front and ISIS espouse a hostile anti-Western Islamist ideology that calls for terrorist attacks against the United States. The leader of ISIS, self-proclaimed caliph Abu Bakr Baghdadi, threatened to launch attacks against the U.S. homeland in July 2012, when he warned Americans: “You will soon witness how attacks will resound in the heart of your land, because our war with you has now started.”[8] Al-Qaeda also formed a new unit of veteran terrorists to recruit some of the Western foreign fighters in Syria and train them to conduct terrorist attacks in the countries in which they hold legal citizenship. This unit, dubbed the Khorasan group by U.S. officials, is embedded in the Nusra Front and is particularly interested in recruiting fighters who hold American passports.[9]

One other concerning detail is the integrity of the naturalization process. Mohamud was in the process of planning his travel to Syria when he became a U.S. citizen. Dzhokhar Tsarnaev became a citizen several months before the Boston marathon bombing, while older brother Tamerlan’s application was pending due to Department of Homeland Security questions about an FBI interview with Tamerlan on possible connections to Chechen terrorists.[10] Faisal Shahzad, who plotted to bomb Times Square, became a citizen about one year before he was arrested.[11] In each of these cases, the radicalization process had begun before naturalization. U.S. citizenship is an honor to be bestowed on those who love America and the principles for which it stands. These recent failures to prevent radical and radicalizing individuals from becoming U.S. citizens, undermines the integrity of the naturalization process. Unfortunately, U.S. Citizenship and Immigration Services is tasked with executing President Barack Obama’s various immigration executive actions, making it unlikely that the agency will have the time or resources to secure the naturalization process.[12]

Congress’s Role in Securing the Homeland

With every week bringing news of another foiled Islamist terrorist plot, the U.S. must ensure that its counterterrorism efforts are as sharp as they can be. Congress must:

  • Maintain essential counterterrorism tools. Support for important investigative tools is essential to maintaining the security of the U.S. and combating terrorist threats. Legitimate government surveillance programs are also a vital component of U.S. national security and should be allowed to continue. The need for effective counterterrorism operations, however, does not relieve the government of its obligation to follow the law and respect individual privacy and liberty. In the American system, the government must do both equally well.
  • Support stronger action against Islamist terrorist groups. The United States and its allies need to take more effective steps to isolate, undermine, and defeat ISIS and the Nusra Front. Greater intelligence and law enforcement cooperation is needed to uncover and neutralize terrorist plots, curtail the flow of foreign fighters to Syria, and monitor the activities of foreign fighters that have returned to the United States and other countries.
  • Ensure security at home. The U.S. cannot rest in its counterterrorism efforts. With a recent spike in Islamist terrorist plots bringing the total to 67 since 9/11, the U.S. must ensure that it is doing all it can to protect Americans, their liberty, and their way of life.

—David Inserra is a Research Associate for Homeland Security and Cyber Security in the Douglas and Sarah Allison Center for Foreign and National Security Policy, of the Kathryn and Shelby Cullom Davis Institute for National Security and Foreign Policy, at The Heritage Foundation. James Phillips is Senior Research Fellow for Middle Eastern Affairs in the Allison Center.

[1] David Inserra and Charles D. Stimson, “Three Terrorist Plots Disrupted in Three Weeks: 66th Islamist Plot Reconfirms Scope of Threat,” Heritage Foundation Issue Brief No. 4386, April 16, 2015, http://www.heritage.org/research/reports/2015/04/three-terrorist-plots-disrupted-in-three-weeks-66th-islamist-plot-reconfirms-scope-of-threat

[2] U.S. v. Mohamud, case no. 2:15-cr-00095-JLG (Oh. 2015), https://s3.amazonaws.com/s3.documentcloud.org/documents/1900046/mohamud-indictment.pdf (accessed April 20, 2015).

[3] Ibid.

[4] Ibid.

[5] Many details are not available in the indictment, such as which military facility in Texas was being targeted, the timeline of events whereby Mohamud returned to the U.S. and began his plotting, and the details of his arrest. These may be held for security reasons or to protect ongoing intelligence operations.

[6] Julia Preston, “F.B.I. Interview Led Homeland Security to Hold Up Citizenship for One Brother,” The New York Times, April 20, 2013, http://www.nytimes.com/2013/04/21/us/tamerlan-tsarnaevs-citizenship-held-up-by-homeland-security.html (accessed April 20, 2015).

[7] Nicholas J. Rasmussen, Director National Counterterrorism Center, “Current Terrorist Threat to the United States,” testimony before the Senate Select Committee on Intelligence, February 12, 2015, http://www.nctc.gov/docs/Current_Terrorist_Threat_to_the_United_States.pdf (accessed April 21, 2015).

[8] James Phillips, “A Resurgent Al-Qaeda in Iraq Threatens U.S. Attack,” The Daily Signal, July 26, 2012, http://dailysignal.com/2012/07/26/a-resurgent-al-qaeda-in-iraq-threatens-u-s-attack/

[9] 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/research/reports/2014/10/the-rise-of-al-qaedas-khorasan-group-what-it-means-for-us-national-security.

[10] Brian Bennett and Richard. A. Serrano, “Tamerlan Tsarnaev’s Citizenship Application Was Pending,” Los Angeles Times, April 21, 2013, http://articles.latimes.com/2013/apr/21/nation/la-na-nn-citizenship-ice-boston-20130421 (accessed April 21, 2015), and Ann O’Neill, “The 13th Juror: The Radicalization of Dzhokhar Tsarnaev,” CNN, March 30, 2015, http://www.cnn.com/2015/03/27/us/tsarnaev-13th-juror-jahar-radicalization/ (accessed April 21, 2015).

[11] “Bomb Suspect’s Citizenship Raises Questions about Naturalization Process,” Fox News, May 4, 2010, http://www.foxnews.com/politics/2010/05/04/times-square-suspects-citizenship-raises-questions-naturalization-process/ (accessed April 20, 2015), and Greg Miller and Jerry Markon, “Radicalization of Times Square Suspect Was Gradual, Investigators Say,” The Washington Post, May 7, 2010, http://www.washingtonpost.com/wp-dyn/content/article/2010/05/07/AR2010050700194.html (accessed April 21, 2015).

[12] David Inserra, “DHS’s Focus on Amnesty a Greater Threat to Security than Budget Impasse,” The Daily Signal, January 26, 2015, http://dailysignal.com/2015/01/26/dhss-focus-amnesty-greater-threat-security-budget-impasse/.


David Inserra

Former Policy Analyst for Homeland Security and Cyber Policy

James Phillips

Visiting Fellow, Allison Center for Foreign Policy Studies