Threat of Homegrown Islamist Terrorism
from Civil Society, Markets, and Democracy Program and Combating Extremism through Civil Society

Threat of Homegrown Islamist Terrorism

An increase in terror incidents involving Islamic radicals who are U.S. citizens is vexing law enforcement officials and posing new questions about the roots of their radicalization.

Last updated September 30, 2011 8:00 am (EST)

Current political and economic issues succinctly explained.


This publication is now archived.


More From Our Experts

The number of terror incidents involving Islamic radicals who are U.S. citizens has seen an uptick in recent years. U.S. citizens have also been involved in some high-profile international terrorism incidents, such as the 2008 attacks in Mumbai, India. This has prompted growing questions about motivations of Islamic radicals in the United States in the decade since the September 11, 2001, terror attacks by al-Qaeda that killed nearly three thousand people. As the list has grown, the question increasingly arises of how to combat Islamist terrorism at home. U.S. law enforcement intelligence is hampered by an underdeveloped relationship with Muslim communities and the inability to readily identify potential terrorists--especially since they often do not appear to need help from international organizations like al-Qaeda to carry out plots.

Islamic Radicalism in the United States

More on:

Terrorism and Counterterrorism

Homeland Security

United States

Race and Ethnicity


Between September 11, 2001, and the end of 2009, the U.S. government reported forty-six incidents of "domestic radicalization and recruitment to jihadist terrorism" that involved at least 125 people, according to a May 2010 Rand Corporation report (PDF). Half the cases involve single individuals, while the rest represent "tiny conspiracies" (PDF), according to congressional testimony by Brian Michael Jenkins, author of the Rand report.

About one-quarter of the plots identified have links to major international jihadist groups like al-Qaeda, according to the Rand report. But a March 2010 Bipartisan Policy Center paper points out an increasing number of Americans are playing high-level operational roles in al-Qaeda and aligned groups (PDF), as well as a larger numbers of Americans who are attaching themselves to these groups.

There had been an average of six cases per year since 2001, but that rose to thirteen in 2009, a worrisome sign to some experts. Still, analysts caution against assuming any large-scale radicalization of the U.S. Muslim population. Cases of Muslims involved in domestic terror plots represent a very small minority of the entire U.S. Muslim community, which ranges somewhere between less than 2 million and upwards of 7 million (U.S. law forbids mandatory questions about religion on the  U.S. Census [WSJ], and polling and other estimates have produced a wide range in population numbers.)

More From Our Experts

"Given the fact that we’re dealing with such a miniscule minority of, in this case, the Muslim population, it’s extremely difficult to craft national policies that affect the tiny minority, or as we would say, statistically detailed distribution," said Richard Falkenrath, a CFR adjunct senior fellow for counterterrorism and former New York City deputy commissioner for counterterrorism.

Sources of Radicalization

As of January 2010, all but two people arrested in the last decade for domestic terror connected to radical Islam have been male. Otherwise, at least three recent think tank reports have concluded that suspects follow no definitive ethnic or socioeconomic pattern, being both immigrant and native-born, and ranging in age from 18 to 70.

More on:

Terrorism and Counterterrorism

Homeland Security

United States

Race and Ethnicity


"The only common denominator appears to be a newfound hatred for their native or adopted country, a degree of dangerous malleability, and a religious fervor justifying or legitimizing violence that impels these very impressionable and perhaps easily influenced individuals toward potentially lethal acts of violence," argues a September 2010 paper by the Bipartisan Policy Center (PDF).

Counterterrorism experts point to online social media sites and charismatic English-speaking preachers, such Anwar al-Awlaki, as a boon for terrorist groups looking to spread their ideology in the United States. The U.S. prison system remains another concern (PBS) for jihadist recruiting. In January 2010, the Senate Foreign Relations Committee issued a report on al-Qaeda, which found that as many three dozen U.S. ex-convicts (PDF) thought to have become radicalized in prison may have attended terrorist training camps in Yemen. In 2005, law enforcement officials foiled a plot to attack numerous sites in California by three Muslim men linked to Jamiyyat Ul Islam Is Saheeh, a militant, prison-based Muslim group started in 1997. A March 2010 FBI bulletin on radicalization in prison says more study is needed. "Authorities must temper their responses with the understanding that religious conversion differs from radicalization," the report says.

Major Terror Cases

Nearly all of the high-profile domestic terror incidents have resulted in convictions (PDF) in U.S. federal courts. Here are profiles of major cases:

Domestic Terror

Jose Padilla. A U.S. citizen on a flight from Pakistan, Padilla was detained in Chicago in 2002 and accused of participating in an al-Qaeda plot to detonate a "dirty bomb" on U.S. soil. Padilla, who converted to Islam while in jail, was labeled an "enemy combatant," held in a military prison, and denied access to civilian courts for over three years. In late 2005, as the Supreme Court was weighing the constitutionality of Padilla’s detention, he was added to a federal criminal case of two other men accused of supplying money, supplies, and recruits for a North American support cell of Islamic extremists, unrelated to the alleged dirty bomb plot. Padilla was sentenced in 2008 to seventeen years in prison.

Detroit Sleeper Cell. Six days after September 11, 2001, police raided an apartment in Detroit, found video footage of tourist sites like Disneyland and drawings that authorities alleged depicted a U.S. air base in Turkey and a military hospital in Jordan. Four legal immigrants, three from Morocco and one from Algeria, were accused of collecting intelligence for terrorist attacks. Three of the men were subsequently convicted, but the fourth was acquitted. The Justice Department later removed the lead prosecutor from the case, saying he knowingly withheld information that could have proved the group’s innocence, which later led to reversal of the convictions.

Faisal Shahzad. A naturalized U.S. citizen from Pakistan, Shahzad attempted to bomb New York’s Times Square with a parked car full of explosives in May 2010. Shahzad was inspired by Pakistani militants and told authorities he was a "fan and follower" of radical cleric Anwar al-Awlaki, but appears to have planned the bombing alone. He plead guilty and was sentenced to life in prison without the possibility of parole.

Nidal Hasan. Virginia-born Muslim and career military psychiatrist Hasan shot and killed thirteen people and wounded nearly thirty in November 2009 at the Fort Hood Army base where he worked. Hasan followed Anwar al-Awlaki’s lectures and sent twenty-one emails to him asking what Islamic law said about Muslim-American soldiers killing their colleagues. Awlaki responded twice. Hasan frequently argued that it was immoral for Muslim-American soldiers to fight against fellow Muslims in Iraq and Afghanistan, and found out he was being deployed shortly before his rampage. He will be tried in military court and an investigating officer has recommended capital punishment.

Lackawanna Six. Nearly a year after September 11, six Yemeni-American childhood friends from a Buffalo, NY, suburb were arrested in what was a "showpiece for the Bush administration’s war on terror" (NYT), and one of the first examples of preemptive justice on terrorism. They attended an al-Qaeda training camp in Kandahar in the spring of 2001, which some in the group claim was motivated by curiosity. All six plead guilty to providing material support for a terrorist organization and were sentenced to seven to nine years in prison. Some have been released, and three will be granted aliases by the U.S. government upon their release for testifying against al-Qaeda.

Fort Dix Plot. Six foreign-born Muslims--including four ethnic Albanians from Macedonia and Kosovo who illegally immigrated, a Palestinian from Jordan turned U.S. citizen, and a legal Turkish immigrant--were arrested in 2007 for a plot targeting the Fort Dix Army base in New Jersey. The arrests were made after a store clerk turned in a video showing them shooting guns and calling for jihad. The group had no apparent connection with any international terror organizations. Five of the six received life prison sentences from a federal court in late 2008.

The Portland Seven. This diverse group of American Muslims in Portland, OR, was charged with attempting to join al-Qaeda and levy war against the United States in a 2002 and 2003 fifteen-count federal indictment aided by the Patriot Act. One fugitive of the group joined al-Qaeda and was killed by Pakistani forces in Afghanistan. The remaining six are serving, or have served, prison time.

Mohamed Osman Mohamud. Somali-born, naturalized U.S. citizen Mohamud penned several articles for the online magazine Jihad Recollections in 2009, and U.S. authorities allege he attempted to connect with terrorists in Pakistan. In November 2010, police arrested Mohamud in Portland, OR, for trying to detonate what he believed to be a car bomb during a Christmas-tree lighting ceremony. The bomb was actually a fake planted by the FBI, and some question whether the sting operation represented entrapment (NYT).

Terror Abroad

Anwar al-Awlaki. New Mexico-born Anwar al-Awlaki was a radical Muslim cleric accused of recruiting for al-Qaeda who increasingly advocated violent jihad. Sometimes called the Osama bin Laden of the Internet, Awlaki corresponded primarily through cyberspace with Fort Hood-shooter Nidal Hasan, a Minnesota group that recruited for al-Shabaab, and three of the September 11 hijackers. His lectures were also mentioned by one of the men convicted in the Fort Dix plot, as well as would-be Times Square bomber Faisal Shahzad. In April 2010, the Obama administration authorized a targeted killing of Awlaki in Yemen. His father acquired two groups of human rights lawyers to challenge Awlaki’s inclusion on a list of people to be killed without trial, but the administration’s order was upheld by a federal judge in December 2010. Awlaki was reported killed in Yemen (CBS) on September 30, 2011, by a U.S. airstrike, which also killed U.S.-born Samir Khan, editor of an English-language al-Qaeda web magazine. The deaths have raised fresh concerns about constitutionality of such operations.

John Walker Lindh. A native Californian, Lindh converted at a local mosque before traveling to Yemen, Pakistan, and Afghanistan to join the Taliban, and was captured in November 2001 as the U.S. military invaded Afghanistan. Due to a plea bargain, Lindh was sentenced to twenty years in prison by a federal court on the condition that he drop claims that he had been mistreated or tortured and that he not speak publicly about the conditions of his sentence.

David Headley. A native of Washington, DC, Headley helped Pakistan-based group Lashkar-e-Taiba identify targets for the 2008 terrorist attacks in Mumbai. Headley was also plotting to attack the Copenhagen offices of the newspaper that published cartoons depicting the prophet Mohammad. After September 11, the Drug Enforcement Administration employed Headley as an informant in Pakistan, despite repeated warnings that he might be a terrorist. Headley plead guilty in 2010 in a U.S. federal court and faces life in prison.

Pakistan Five. Five U.S. citizens who reached out to extremists through YouTube were arrested in Pakistan on their way to fight against U.S. troops in Afghanistan with a jihadist group. The young men of Pakistani, Egyptian, Ethiopian, and Eritrean decent--who attended the same northern Virginia mosque--maintain they traveled for a wedding and to help Muslims displaced by the war in Afghanistan. Pakistani courts sentenced them to ten years in prison.

Somalia Plot. Fourteen Somali-Americans were charged in August 2010 with providing material support and recruits for al-Shabaab, an Islamic militant organization fighting an insurgency in Somalia. Of the group, most were in Somalia at the time of the indictment.

Shirwa Ahmed. In October 2008, Shirwa Ahmed, a Somalia-born U.S. citizen, drove a car full of explosives into a government compound in northern Somalia, killing himself and more than twenty people. Speaking at the Council on Foreign Relations in February 2009, FBI Director Robert S. Mueller said Ahmed was radicalized in his Minnesota hometown of Minneapolis.

Policy Implications

An October 2010 report from the Washington, DC-based American Security Project suggests U.S. policy find strategies that address the "deep-seated perceptions and attitudes" among the Muslim and non-Muslim population that help "fuel the alienation cycle that has helped to make a small but increasing number of Americans more susceptible to extremist ideology."

Some experts say the government needs to do a better job with Muslim communities, perhaps their best source of intelligence on terrorist plots, and should avoid heavy-handed tactics and civil liberties abuses that jeopardize trust building. For example, following the 9/11 terrorist attacks, the FBI began routinely interviewing Arab and Muslim men in the country, which garnered criticism from civil liberties advocates that it unfairly targeted entire communities.

But engaging Muslim communities presents challenges. "The U.S. government runs major national programs, but it’s not present in a serious, sustained way in all the communities of interest," says CFR’s Falkenrath. "The only government agencies that really are [present] are the local agencies: health departments, education departments, police departments, fire departments. As a practical matter, if you really wanted to do something in this (what is called counter-radicalization), you’d need to find a way to incorporate the government agencies at the local level into such an effort."

Nadia Roumani, director of the American Muslim Civic Leadership Institute, also stresses the importance of coordinating among agencies. "Oftentimes, especially on this issue, there will be one strategy that’s been taken by local law enforcement and a different strategy taken by the FBI and a different strategy taken by [the Department of Homeland Security]," she noted in a July 2010 panel discussion (PDF). "And then the community’s confused [on] who to engage and how these are all connecting." Law experts Tara Lai Quinlan and Deborah Ramirez suggest developing a "nationally coordinated law enforcement-community partnership infrastructure" (HuffingtonPost) similar to what is being done to combat radicalism in the United Kingdom (PDF).

Roxanne Emadi contributed to this report.


Top Stories on CFR

South Africa

The provincial and national elections on May 29 come amid waning support for the ruling African National Congress thirty years after South Africa transitioned to democracy.


In his inaugural address, Taiwan’s new president Lai Ching-te signaled broad continuity on cross-strait issues. China, however, is likely to respond with increased pressure. 

Election 2024

The European Union (EU) began implementing the Digital Services Act (DSA) this year, just in time to combat online disinformation and other electoral interference in the dozens of elections taking pl…