Militant Extremists in the United States

Militant Extremists in the United States

Violent acts by homegrown militant extremists in the U.S. have declined, but "lone wolf" attacks are on the rise. The post-9/11 legal and political landscape poses new challenges to law enforcement authorities seeking to prevent such attacks.

Last updated February 7, 2011 7:00 am (EST)

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The January 2011 shootings--in which a lone gunman killed six people at a Tucson, Arizona, shopping center--served as a reminder of the threat posed by militant extremism in the United States. Similar acts of violence in the last few years--such as the suicide plane crash into an IRS building in Texas and the 2009 shooting at the U.S. Holocaust Memorial Museum--have brought renewed attention to the dangers posed by fringe political extremism. Although the frequency of these types of attacks has decreased in recent years, "lone wolf" violence is on the rise. The FBI is particularly concerned by such threats because they are performed by individuals who are unaffiliated with any larger movement and are, therefore, hard to detect. As with the case of Tucson shooter Jared Lee Loughner, it is difficult for authorities to determine whether such an act of violence falls under the legal definition of "domestic terrorism," a determination that invokes much harsher sentencing guidelines. Some experts criticize a lack of consistency in the way U.S. domestic terrorism laws are applied, which can lead to dissimilar procedures and outcomes for similar cases.

Violent Extremism or ’Domestic Terrorism’?

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Since September 11, the threat of internationally based Islamic extremist networks has dominated concerns of Homeland Security officials. And while authorities say the threats posed by homegrown Islamic extremism is growing, the FBI has reported that roughly two-thirds of terrorism in the United States was conducted by non-Islamic American extremists from 1980-2001; and from 2002-2005, it went up to 95 percent.

With the enactment of the Patriot Act in 2001, the legal definition of "terrorism" was expanded to include domestic as well as international terrorism. However, alternative definitions still exist at the FBI, Justice Department, Homeland Security Department, and Defense Department. Some descriptive terms (such as "sub-national," "pre-meditated," "noncombatant," etc.) are present in one definition and absent in others. Furthermore, many law enforcement groups, like the FBI, use the labels of domestic terrorism and violent extremism interchangeably. One consequence of this practice is a lack of uniformity in the way domestic terrorist activities are prosecuted. In an effort to improve federal terrorism laws, a Syracuse University-sponsored watchdog organization compared the number of terrorism cases listed by three entities--the courts (310), the prosecutors (508), and the National Security Division (253)--and found that from 2004-2009 only 4 percent of cases were classified as terrorism on all three lists. This suggests that the agency that made the designation, not the facts of the case, determined whether a suspect was prosecuted as a terrorist and, therefore, may have received a harsher sentence. The same report found "little public evidence that the Obama administration has launched a significant effort to deal with the continuing criminal enforcement flaws."

A Spectrum of Militancy

The worst case of domestic extremist violence was the 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City that killed 168 people. In the twenty-five years prior, the United States experienced an average of forty-eight such attacks per year. Since 1995, the average attacks per year declined to nineteen. However, the percentage of attacks perpetrated by individuals acting alone, characterized by law enforcement as "lone wolf" offenders, has increased roughly five-fold (see chart below). Defending against these types of attacks is a daunting task for the FBI and police.

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The FBI divides domestic extremists into four broad categories, including left-wing, right-wing, single issue groups, and homegrown Islamic. (Read this CFR Backgrounder on the threat of homegrown Islamist extremists.) The lone offender phenomenon spans all categories, and the classifications have other overlapping characteristics as well.

LONE OFFENDERS: Violence by lone offenders (WSJ) may pose the most immediate threat in the United States. According to an FBI report on terrorism, the lone wolf label refers to individuals "who commit acts of violence outside of the auspices of structured terrorist organizations or without the prior approval or knowledge of these groups’ leaders." A Department of Homeland Security study found that attacks by individuals constituted one-third of all extremist acts of violence since 1995, up from just 6.5 percent in the twenty-five years prior. Recent high-profile cases of these attacks include those by Jared Lee Loughner (NYT), James von Brunn (WSJ), and Abdulhakim Mujahid Muhammad. Because of their isolation from organized extremist groups, lone wolves are particularly hard to track for intelligence agencies. However, their independence often makes them less effective than members who are well connected to large networks.

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Graph: Percent of U.S. Terrorist Attacks by Individuals, pre- and post-Oklahoma CitySource: START

LEFT-WING GROUPS: The FBI states leftist extremist groups "generally profess a revolutionary socialist doctrine and view themselves as protectors of the people against the "dehumanizing effects" of capitalism and imperialism." From 1960 to the mid-1980s, most acts of extremist violence were committed by leftist factions like the Weather Underground. A wellspring of disaffected, radical youth with ideological roots in the civil rights, women’s liberation, and anti-war movements provided these groups with much of their militant fervor. However, broad left-wing violence has been in a marked decline since the fall of the Soviet Union and a successful FBI infiltration campaign in the mid-1980s.

SINGLE-ISSUE GROUPS: Single-issue extremists attack targets that embody distinct political issues like environmental degradation, abortion, genetic engineering, or animal abuse. These groups are usually composed of small, autonomous cells that are hard to infiltrate because of rigid secrecy. According to the FBI, so-called eco-terrorists and animal rights groups like the Earth Liberation Front have committed over two thousand crimes and caused losses of over $110 million since 1979. Ecological extremism (BaltimoreSun) gained particular notoriety in the 1990s, and in 2004 the FBI declared these groups the No. 1 domestic terrorism threat. Anti-abortion extremists are responsible for seven murders, forty-one bombings, and 173 acts of arson in the U.S. and Canada since 1977, according to the National Abortion Federation, an abortion rights group. While much of this violence peaked in the 1990s (PDF), the 2009 murder of Dr. George Tiller (NYT) served as a reminder of the threat still posed by these factions.

RIGHT-WING GROUPS: The most recent swell of extremist violence began to emerge from right-wing militants in the late-1980s and 1990s. According to a 2005 FBI report on terrorism, these groups, which are "primarily in the form of domestic militias and conservative special interest causes, began to overtake left-wing extremism as the most dangerous, if not the most prolific, domestic terrorist threat to the country." Right-wing extremists champion a wide variety of causes, including racial supremacy, hatred and suspicion of the federal government, and fundamentalist Christianity. The Southern Poverty Law Center, which tracks the activities of hate groups, suggests militia groups declined every year since 1996 but have seen a dramatic resurgence since 2008.

Civil Liberties and Counterterrorism

Following the Church Committee hearings of 1975 and the exposure of several illegal U.S. intelligence programs, U.S. lawmakers instituted a number of legal reforms to safeguard civil liberties, including the 1978 Foreign Intelligence Surveillance Act or FISA. This legislation created strict procedures for reviewing government requests for the electronic surveillance of Americans and resident aliens, and sought to end the practice of warrantless wiretapping. It placed the legal burden of proof on the intelligence community to demonstrate that the subject of surveillance is "a foreign power or agent of a foreign power."

Alternative definitions [of what legally constitutes terrorism] still exist at the FBI, Justice Department, Homeland Security Department, and Defense Department.

However, after the September 11 attacks, the FBI shifted its directive (CNN) from law enforcement to terrorism prevention--returning its emphasis to proactive domestic surveillance. The public fear of another large-scale attack ushered in a new privacy-security paradigm, and with it came legislation aimed at broad national security reforms, such as the Patriot Act, the Homeland Security Act, the Intelligence Reform and Terrorism Prevention Act (PDF), and the 2008 FISA Amendment Acts. But despite this overhaul, CFR’s Richard Falkenrath suggests, "The federal government has a quite limited domestic intelligence program and capability. The government does not have an unfettered right to collect information on Americans. It’s a very complicated legal and executive order framework, which governs when and how the government can collect information of potential threats domestically."

The Domestic Intelligence Infrastructure

September 11 was a seminal event for U.S. intelligence culture. Prior to the attack, critical components of the intelligence infrastructure like the CIA, FBI, and NSA were not sharing essential information. The 9/11 Commission Report cited a number of reasons for this including structural barriers, divided management, lack of common practices, and excessive secrecy. In their effort to reform the system, lawmakers deemed terrorism prevention a national priority that required the integration all elements of the intelligence infrastructure, including local and state entities as well as dedicated federal agencies like the FBI. To fulfill their new role, local police commanders promoted the adoption of "intelligence-led policing" (PDF), a philosophy emphasizing future-oriented, risk-based intelligence.

The conventional wisdom from law enforcement officials is that prevention requires active, exploratory intelligence gathering. But despite the new emphasis, CFR’s Falkenrath says the U.S. domestic intelligence system "is still really built around a framework that requires ’predication,’ or evidence of a crime that has occurred or is about to occur. This framework works well in a criminal justice setting, but it really struggles when you know there are real threats that don’t have clear predication."

In an open-source review (PDF) for the Department of Homeland Security in 2009, the RAND Corporation mapped the domestic intelligence network to identify all the components "involved in the collection, analysis, and sharing of information about individuals and organizations in the United States." This study identifies three principle categories focused on domestic extremists:

  • Department of Homeland Security. Formed in 2002, DHS is a cabinet-level department that performs a vast number of domestic intelligence activities and initiatives. The Office of Intelligence and Analysis is the core element of its intelligence function. DHS also operates the National Operations Center, which collects and fuses information from more than thirty-five public and private agencies. In addition, Information-Sharing and Analysis centers or ISACs are an assortment of public-private partnerships designed to protect critical physical and electronic infrastructure from terrorist attacks. For example, DHS launched a cybersecurity operation center in New York in November 2010.
  • Department of Justice. The Federal Bureau of Investigation is the government’s lead agency for domestic intelligence and counterterrorism, but the DoJ also includes the DEA, U.S. Attorneys Offices, U.S. Marshals Service, and the Bureau of Alcohol, Tobacco, Firearms, and Explosives. The FBI intelligence mission is managed at the National Security Branch which, among other things, manages the National Joint Terrorism Task Force and the Terrorist Screening Center.
  • State, Local, and Private-Sector Groups. The FBI-led Joint Terrorism Task Force and the DHS-supported Fusion Center program are the most prominent federally directed, multiagency initiatives. Both programs use intelligence from multiple entities to leverage information-sharing potential. However, the FBI task force is always the lead agency for domestic terrorism investigations, as demonstrated in the the January 2011 MLK Day attempted-bombing in Washington state. On the other hand, fusion centers may be focused on any number of other concerns outside the realm of terrorism, such as organized crime, immigration, and natural disasters.

The Road Ahead

"We’re at a point where you have to start asking hard questions about changing the law, and/or the executive orders that interpret the law, to be more permissive," -- CFR Adjunct Senior Fellow Richard Falkenrath.

Militant extremism in the United States continues to provide grist for the national debate on a number of policy areas. The shootings in Tucson revived the issue of gun control once again, highlighting some of the nation’s controversial firearm legislation--like the Arizona law allowing citizens to carry concealed weapons without a permit. In addition, public discussion continues over the legal definition of domestic terrorism and whether it is applied equitably. Questions also remain as to whether the United States has lessons to learn from the counterterrorism experiences of other countries. For instance, should it create an independent domestic intelligence agency (PDF) similar to Britain’s MI-5, which does not incorporate a law enforcement function like the FBI?

Efforts to counter homegrown militancy will also continue to drive a conversation on civil liberties.  Liberal groups like the American Civil Liberties Union advocate for stricter legal guidelines, "oppos[ing] the broad definition of terrorism and the ensuing authority that flows from that definition." On the other hand, proponents of assertive enforcement capabilities, like CFR’s Falkenrath, raise concerns over potentially excessive regulation. "We’re at a point where you have to start asking hard questions about changing the law, and/or the executive orders that interpret the law, to be more permissive."

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