Homegrown Terrorism Research Paper

A review of the empirical literature demonstrates that homegrown terrorists currently pose a threat to public safety. These threats are dynamic however and change over time. In addition, policy interventions and strategic tactics often have unintended consequences. Sometimes these interventions have created backlash effects that led to greater numbers of crimes. This research paper first discusses how homegrown extremists pose a threat and then illustrates how it has changed over time. Second, the paper outlines the nature and scope of the current danger posed by homegrown terrorists and extremists. It then discusses how policy makers, law enforcement personnel, and crime analysts should carefully monitor the homegrown threat and consider the unintended consequences of their proposed responses to these extremists. Finally, note that this research paper includes new material and draws from materials published in two 2009 articles (Freilich et al. 2009a, b).

Key Issues

Homegrown terrorists and extremists pose a risk to the American community. Recently, attention has focused on American supporters of Al-Qaeda and related ideologies, because of the devastating attacks committed on September 11 and its desire to strike again within the United States. However, LaFree et al. (2006) found that the United States also faces other homegrown threats. Hewitt (2003; see also Smith 1994) found that between 1954 and 2000, over 3,000 terrorist incidents were perpetrated in the United States, many by non-Islamic jihadist homegrown terrorists such as far-rightists, Puerto Rican nationalists, Jewish extremists, Black nationalists, and animal and ecoterrorists. These acts claimed over 700 lives and caused hundreds of millions of dollars in damage. More recent research indicates that the number of incidents occurring in the United States might be higher (Freilich et al. 2012).

A review of the accumulated empirical evidence finds that homegrown terrorist threats are not static. Smith’s (1994) study of terrorist strikes in the United States found homegrown far-left groups to be the most active in the 1970s. Carlson (1995) surveyed police chiefs in large-sized American cities (>100,000) in the early 1990s. He asked the chiefs to rank the top four groups that, in their opinion, were most likely to commit a terrorist act within the next 2 years. Despite the celebrated nature of the 1993 Trade Center bombing, police chiefs did not think that Middle Eastern terrorists posed the greatest threat. Instead, homegrown antiabortion perpetrators and white supremacists were rated the two greatest threats. Riley and Hoffman’s (1995) RAND survey of state and local agencies over 2 years in the early 1990s similarly found that issue-specific homegrown organizations (e.g., antiabortion) and right-wing groups posed the greatest terrorist threat. Freilich et al. (2009) more recent survey of state police agencies found that almost all respondents strongly agreed that Islamic jihadists and their American supporters were the top national security threat and most strongly agreed or agreed that they were a significant threat to state security. Importantly, far-right and animal/environmental rights homegrown extremist movements were also seen as representing a severe threat to both national security and to the security of individual states.

These results demonstrate that homegrown terrorism threats change over time. Carlson’s research from almost 15 years ago identified homegrown antiabortion activists as the greatest threat. Freilich et al. (2009) found that state police agencies, however, do not currently rate antiabortion activists as posing a great threat to either national security or their state’s security. The attacks of September 11 have clearly impacted concerns about the potential threat of Islamic extremists in the United States. While Smith’s (1994) domestic terrorism study found homegrown far-left groups to be the most active in the 1970s, currently state police agencies do not rate far-left groups as a major threat on either the national or state level.

Relatedly, the strength of individual groups and the larger homegrown movements they belong to also evolves over time. These extremist and terrorist groups and their external environment are dynamic. For example, research finds that the homegrown far-right militia movement was impacted by the Oklahoma City bombing, forcing many individuals to leave the movement, others to join, and some to go underground or seek other extremist organizations in fear of government infiltration (Chermak 2002). Extremist organizations and terrorist groups must adapt to changes occurring in their external environment. Research (Freilich et al. 2009; Rapoport 1992) shows that most terrorist and extremist groups are unable to adapt and therefore fail in a relatively short time.

Empirical evidence also finds that the rise and fall of homegrown extremist organizations are linked to critical events and organizational-level variables that enhance or disrupt the group. Freilich et al. (2009) identified factors that produced growth and decline within four homegrown far-right extremist organizations (the National Alliance, the Aryan Brotherhood, Public Enemy Number 1, and the Oklahoma Constitutional Militia). The groups that grew did do because they (1) had able leadership that set forth a clear ideological message and goals, (2) undertook concrete actions to further their ideology and goals and had the finances necessary, (3) took advantage of political opportunities, and (4) were internally cohesive. However, the groups declined because of organizational instability and/or responses by law enforcement and nonstate actors, such as watch groups. The fall/ decline of a particular group likely affects other groups or supporters in the same movement. For example, the decline of one far-right group often provides political openings for another extremist organization to grow and prosper. Another example is law enforcement operations that eliminate violent extremists. Such actions could unintentionally outrage and further radicalize other extremist groups to turn to violence (Freilich et al. 2009).

Current Threat

The United States Extremist Crime Database (ECDB) is a unique, open-source, relational database. The ECDB is funded by the Department of Homeland Security through the National Consortium for the Study of Terrorism and Responses to Terrorism (START). It tracks ideologically motivated and routine/nonideological violent and financial crimes committed by homegrown movements seen as representing the greatest threat to American public safety: far-rightists, Al-Qaeda supporters, and animal and environmental rights extremists (Freilich et al. 2009). Definitions/descriptions of these movements are set forth in Freilich et al (in press) work and are available upon request. The ECDB collects information on multiple units of analysis. The ECDB’s inclusion criteria are based upon a criminological approach, and the ECDB is different than other terrorism databases because it includes a broader array of illegal acts. For an incident to be included in the ECDB, it must satisfy a two-prong test. The first prong is behavioral and requires that an illegal violent act or financial scheme must have been committed inside the United States. The second prong is attitudinal and requires that, at the time of the incident or scheme, at least one of the suspects who committed the act must have subscribed to a far-right, Al-Qaeda-influenced, or extremist animal or environmental rights belief system (Freilich et al. in press).

The ECDB has identified thousands of criminal incidents committed by homegrown far-right extremists between 1990 and 2010. These crimes range in important ways, such as the level of violence imposed on victims, the number of suspects involved, and the motivational circumstances underlying each incident. Far-right extremist crimes include hate crimes, attacks on abortion providers, and foiled terrorist plots, as well as financial crimes and cases involving illegal firearms and other weapons.

According to the ECDB, homegrown far-right extremists committed over 370 homicide incidents in the period spanned by the data. Over 40 % of these homicide events were ideologically motivated (and thus most akin to terrorist attacks), and another 20 % were nonideological but were still movement related (such as an internal killing over drugs or a woman). These homicides varied both spatially and temporally. Homegrown far-rightists also killed close to 50 law enforcement officials in the line of duty between 1990 and 2010. These incidents involved federal, state, or local police officers, correctional officers, private security guards, and a judge (Freilich et al. in press).

Smith and Damphousse’s (2009) American Terrorism Study (ATS) documents the tremendous property damage and financial losses that environmental and animal rights attacks have caused in the United States. Indeed, one group “The Family” committed 21 arson and “ecotage” attacks between 1995 and 2001. The group’s most serious act was an arson attack at the Vail ski resort in the late 1990s that caused over $25 million dollars in damage.

The ECDB was still involved in data collection on crimes committed by eco – and animal rights extremists when this research paper was being prepared, and thus the results are not finalized. Nonetheless, a preliminary examination indicates that these homegrown extremists have committed over 230 violent (i.e., bombing and arsons) incidents between 1995 and the present (Freilich et al. 2012). In addition, the ECDB is investigating a few violent acts committed by possible supporters of extremist animal and environmental rights movements that targeted persons. This is important because many academics and others conclude that this type of homegrown extremist has intentionally avoided harming persons (Amster 2006; Cothren et al. 2008; Taylor 1995). These incidents that may have involved animal and environmental rights extremists who targeted persons include the

Unabomber’s letter bomb attacks, the murder of a Red Bluff police officer by a self-proclaimed anarchist who also criticized corporate malfeasance including their harmful actions against the environment, a car bomb attempted murder of a veterinary officer, and the firebombing of a car belonging to a University of California, Santa Cruz scientist that resulted in injuries to both of his feet.

Importantly though, a review of the empirical literature thus far indicates that research on homegrown terrorists has focused mostly on Al-Qaeda supporters and other similar extremists (see below) or far-right extremists. Gruenewald et al. (2009) identified over 320 studies on far-right-wing extremism and political crimes in thefields of criminology, political science, sociology, and terrorism, and most of the current studies focus on Al-Qaeda supporting networks. Conversely, a review found many fewer studies on animal/environmental rights extremists. Future research needs to focus on eco – and animal rights homegrown extremists and study them more systematically.

Again, the ECDB also tracks crimes committed by supporters of Al-Qaeda and groups involved in local jihads across the globe. Many of the perpetrators of these crimes are homegrown extremists. Here too, the ECDB is still involved in data collection. But, a preliminary examination indicates that these extremists have committed over 25 fatal (i.e., the suspect killed others, was killed by police, or committed suicide) incidents since 1990. In addition, in this period, the ECDB identified a few honor-killing incidents, as well as scores of foiled plots in the United States (Freilich et al. in press).

In addition to ideologically motivated violent crimes, homegrown extremists have also committed nonviolent crimes that have harmed US security. Far-right homegrown extremists committed over 430 “financial schemes,” while Al-Qaeda and other similar extremists committed over 100 financial or material support schemes since 1995. These schemes were worth over 600 million dollars. Since data collection and coding is ongoing, this number may change (Freilich et al. in press).

A preliminary descriptive analysis of ECDB data of financial schemes prosecuted in federal court in 2004 reveals that far-right and Al-Qaedainfluenced and similar extremists in the USA engage in different types of financial schemes, follow distinct modus operandi, and are prosecuted for a variety of both financial and nonfinancial crimes (Belli 2011). Despite these differences, a common trend was identified, that is, the involvement of non-extremist accomplices who provided useful resources for the crime commission process.

With respect to the far-right, the findings suggest that these may be individuals with specialized skills and know-how who provided professional services and expertise on a variety of issues (e.g., tax preparation, business ventures, financial and legal counseling). Al-Qaedainfluenced and similar extremists seem to have relied on non-extremist accomplices for a diverse set of reasons, for example, as middlemen to conduct wire transfers and manage bank accounts, couriers for cash smuggling, and nominees to set up storefront businesses (Belli 2011).

A comparison of financial schemes, crimes, and techniques revealed significant differences in the financial criminality of far-rightists and Islamic extremists. Far-rightists engaged mostly in tax avoidance schemes as a form of antigovernment protest. These schemes were perpetrated using techniques that require both proactive and passive behaviors. Proactive behaviors included filing false tax documents, underreporting income, marketing antitax packages, using bogus trusts, and setting up offshore “shell” corporations. Passive behaviors included ideologically motivated tax refusal, that is, a popular crime of omission that involves the failure to file an income return or to pay employment taxes on the basis of misinterpretations of tax laws and the constitution, usually rejected as “frivolous arguments” by US courts.

The majority of Al-Qaeda-influenced and similar extremist-related schemes involved “money-dirtying” and money-laundering strategies for self-financing purposes. Money dirtying (the reverse of money laundering) refers to the process of using money raised legitimately (e.g., through donations or legitimate investments) for illicit purposes (e.g., terrorism financing). Although there are some similarities between money-laundering and money-dirtying strategies, there are also at least two important differences: (1) the source of the money, that is, criminal in the former (e.g., drug dealing, tax evasion, cigarette smuggling) as opposed to either legitimate or criminal in the latter (e.g., legitimate business revenues, charitable donations), and (2) the goal, that is, transforming “dirty” money into expendable income as opposed to channeling funds of any origin to individuals or groups to enable acts of terrorism. To carry out these schemes, Al-Qaeda-influenced and other Islamic extremists made ample use of traditional money transfer mechanisms both domestically and internationally (e.g., wire transfers, cash deposits, checks). They also used simpler methods that avoid leaving paper trails, like conducting transactions in cash and physically transporting money across borders.

There were also differences in the way far-right and Islamic extremist financial crime cases were handled by federal prosecutors. Comparing criminal charges in federal indictments revealed that far-right cases were usually prosecuted for typical financial crime offenses (e.g., tax evasion, mail fraud, money laundering), whereas suspects in alleged terrorism financing cases were indicted for a variety of criminal offenses, ranging from money laundering to providing material support to a foreign terrorist organization (FTO), immigration fraud, RICO conspiracy, and false statements.

Finally, a recent report using ECDB data compared the organizational differences between violent and nonviolent hate groups (Chermak et al. 2013). This study used the Southern Poverty Law Center’s (SPLC) annual Intelligence Report and Klan Watch publications to produce a list of hate groups in the United States (over 6,000 hate groups) and then focused on organizations that existed for at least 3 consecutive years (over 500 groups). Two hundred seventy-five (275) groups were then randomly selected to study in depth. Groups were categorized as violent or nonviolent.

The research revealed that 21 % of the 275 farright hate groups included in the study had members who had committed at least one violent criminal act. Based on findings from a number of statistical models, there appear to be several indicators that were related to a group’s propensity for violence even when controlling for other significant predictors. Age and size were related to a group’s propensity for violence. That is, as groups increased in the number of years in existence or in the number of their members, the likelihood of them being involved in violence increased. This result makes sense as groups have an opportunity to learn over time. The significance of group size may be that simply having more members increases the odds that at least one individual will be linked to a violent act. Larger organizations also have a more diverse body of members who bring different skills and expertise, and this diversity may allow them to evade capture for a longer period of time and thus provide the opportunity to commit more violent crimes.

Groups that published ideological literature, such as newsletters or pamphlets, were significantly less likely to be involved in violence. Such literature is used to attract potential members to the organization, and perhaps these groups realize that the publication of their rhetoric will bring increased attention to their group and thus decrease the likelihood of being involved in violence. Groups that had some specific conflict with another group, had charismatic leaders, advocated for leaderless resistance tactics, and were headquartered in the West and Northeast (compared to groups in the South) were significantly more likely to be involved in violence. Policy makers must carefully monitor political extremists and consider the unintended consequences of their proposed interventions.

These findings suggest that law enforcement intelligence and analysis have an important role to play in countering terrorism. First, the ECDB’s preliminary financial findings have important policy implications. They provide evidence that political extremists today engage in criminal behaviors that have traditionally been associated with profit-driven crime for various reasons and using different methods. In addition, the differences in the modus operandi and goals pursued highlight the importance of conducting systematic analyses of crime patterns using an “all-crimes/all-threats” approach to improve threat assessment and prioritization strategies. Lastly, they highlight the need to investigate the role of non-extremists as well as the nature and scope of their interactions with political extremists, as they may provide crucial resources in the form of knowledge, skills, and contacts.

Again, another important obstacle for law enforcement and analysts to overcome is to understand that identifying the homegrown threats that should be prioritized is like hitting a moving target. Analysts must engage in dynamic analyses (Freilich et al. 2009b; Smith 1994). Changes in contextual and organizational factors may cause a homegrown movement to increase or decrease in strength and potential to commit violent acts. Paying attention to such changes will allow law enforcement to better assess a movement’s threat level as it changes, differentiate between truly dangerous groups and less dangerous groups, differentiate between immediate versus potential future threats, and develop policies to best address these threats (Chermak et al. 2009; Duffy and Brantley 1997; McGarrell et al. 2007).

Presently, different types of counterterrorism strategies have been implemented to reduce the number of terrorism attacks in the United States and abroad. Most strategies are “hard control” measures, such as retaliatory attacks, increasing punishments and using law enforcement measures to “crack down” on certain active groups. Lum et al. (2006, p. 22) conclude in their systematic review that there are few positive results: “Many effects are close to, or cannot be statistically discerned from, a zero effect.”

A review of recent empirical research supports two conclusions. First, previous studies have found that responses by both the state and nonstate actors may contribute to the decline of specific homegrown terrorist or extremist groups. Smith (1994, p. 91; see also Hamm 1993) concludes that homegrown far-right skinhead groups declined in the United States in the 1980s because of a “double barreled blast of aggressive federal criminal prosecutions and private civil rights attorneys.” Hamm (2007) reached similar conclusions about the demise of the homegrown Arizona Patriots (see also Hewitt 2003).

Importantly, such responses, although contributing to declines in these groups, may also have unintended consequences. For example, Hamm’s (2007) important analysis examining terrorist involvement in traditional crime discusses how terrorist groups seek traditional means of funding until such funding is unavailable. Groups then adapt and seek other sources of revenue. Hamm examines the effects of a crackdown on the IRA’s efforts to raise money. In the 1970s, law enforcement shut down the IRA’s fund-raising efforts in the United States, but this success increased their reliance on other sources of revenue. This shift may have also increased the harm caused by the organization as it moved to more traditional criminal and organized crime activities to finance operations, including bank robberies, smuggling goods and weapons, and extortion.

Lum et al. (2006, p. 26) systematic review evaluates several types of counterterrorism measures and also finds that such interventions often produce unintended and counterintuitive findings. For example, the implementation of metal detectors in airports were effective in decreasing airport hijackings, but caused displacement effects and increased the use of other types of terrorism, such as kidnappings, assassinations, and bombings.

Similarly, Freilich et al. (2009a) found that after the homegrown far-right National Alliance and the Aryan Brotherhood imploded for various reasons after the deaths of their well-known leaders, other groups, such as skinhead organizations, seemed to benefit. They concluded that groups within a larger movement are interrelated. Strategies that might mitigate activities against only one part of a movement may result in unanticipated consequences to other parts of that movement.

Relatedly, it seems obvious that successful law enforcement operations can eliminate a group or individuals that have engaged in crimes. This appears to bolster deterrence and incapacitation views that call for harsh responses to extremist groups. Many watch groups call for firm government actions against extremist organizations (Chermak 2002; Freilich 2003).

A review of empirical research in this area also suggests that there are sometimes unintended consequences to law enforcement responses. Perceived harsh government and police actions may lead to consciousness raising (Dobratz and Shanks-Meile 1997) that outrages the wider homegrown movement and causes a backlash. Other extremist groups and the movement at large may grow, and individuals and groups may become further radicalized and turn to violence. A growing number of studies find that harsh government responses to terrorism often have no deterrent impact and sometimes lead to a backlash (LaFree et al. 2009; Pridemore and Freilich 2007). For example, Lum et al. (2006) systematic review of the impact of counterterrorism strategies concluded that retaliatory strikes after a terrorist incident (i.e., the United States attack on Libya in 1986 in response to a bombing in Berlin) actually led to additional attacks.

Similarly, Freilich et al. (2009a) found that the racist Aryan Nations group capitalized on the killings of Gordon Kahl and Robert Mathews by law enforcement in the 1980s and the organization’s popularity increased. In addition, Mathews partially created the notorious group “The Order” – the premiere domestic terrorist group in the 1980s (responsible for five murders and spectacular armored car robberies) because of anger over Kahl’s death. The National Alliance, the militia movement, and other far-right groups grew in reaction to the government’s excesses at Waco and Ruby Ridge in the early 1990s.

Alternative Policies

Based upon a review of the empirical findings in this area, we conclude that the authorities must strike a careful equilibrium. The government must balance a carefully calibrated campaign that eliminates dangerous homegrown groups and stresses that violence will not be tolerated, with responses that avoid outraging and possibly increasing crime from the larger movement. There are several options to consider. First, law enforcement should only use deadly or harsh responses as a last resort. For instance, harsh government actions at Waco and Ruby Ridge in the early 1990s that led to the death of homegrown cult members and far-rightists outraged the antigovernment far-right. Most observers conclude that these harsh policies led to a backlash and fueled the growth of the paramilitary right (Chermak 2002; Freilich 2003). Conversely, the ADL (2003) explains that law enforcement’s nuanced and patient response that allowed far-right extremists to save face led to a peaceful resolution of sieges in Montana in 1996 and in Texas in 1997.

The government should consider accompanying harsh law enforcement actions against violent groups with “outreach” programs to nonviolent wings of extremist movements. These strategies should encourage members of the movement to forsake illegal behaviors in favor of participation in the political system or other legal activities. Jones and Libicki’s study found that 43 % of 268 terrorist groups worldwide – the largest category – ended because of a transition to the political process. Significantly, F.B.I. agents charged with monitoring domestic extremists have made similar arguments. Agents Duffy and Brantley (1997) created a typology of four categories of homegrown far-right militia groups that ranged from noncriminal to organizations that conducted serious – for example, homicide and bombings – crimes. Duffy and Brantley (1997, p. 2) urged local police to open a dialogue with leaders from the two nonviolent categories “so that the two sides can voice their concerns and discuss relevant issues in a nonconfrontational way.”

These strategies should be used more frequently, especially when law enforcement is involved in crackdowns on specific movements. These outreach policies could be modeled after law enforcement efforts to build bridges in immigrant communities that are suspicious of the government (Clarke and Newman 2006; Freilich and Chermak 2009). Newman and Clarke (2008) recently set forth steps that police agencies could take to reduce tension with migrant communities that have come under suspicion because a few terrorists, such as the 9/11 hijackers, used them to fit in. These steps included assigning community police agents to solely work with migrant communities, taking advantage of ethnic media outlets to communicate with the larger community, and clearly publicizing the police agency’s mission and policies. Similar strategies could be undertaken with the more moderate portion of homegrown extremist movements. In addition to initiating dialogue with nonviolent groups, agencies could assign officers to appear on extremist media outlets. Such campaigns should explain the government response and note that it is only directed at those who commit crimes. Authorities should reassure noncriminal members of the movement that their rights will be protected and encourage them to focus on lawful activities while stressing that violence will not be tolerated.

While there are hard-core individuals who have no interest in pursuing change through legitimate processes, it is also true that most extremist individuals and groups do not engage in violence or terrorism themselves. Further, some who end up engaging in terrorism are reluctant participants and are not strongly committed to an extremist ideology. McGarrell et al. (2007) discuss how most (nearly 70 %) of the individuals who were detained as terrorists or linked to a series of bombings were not ideologically committed.

Finally, backlash effects are usually found when a government takes action after a crime or terrorist act has been committed. Strategies that prevent these crimes from happening by such methods as using situational crime prevention to prevent groups from raising funds and furthering their objectives (Clarke and Newman 2006; Freilich and Newman 2009; Hamm 2007; Newman and Clarke 2008) may preempt the harsh police responses to these crimes and thus avoid backlash effects.

Conclusion

This research paper provides an overview of the threat of homegrown terrorism in the United States. Despite the considerable investment in the study of the terrorism that has occurred following the September 11 attacks, there is still little known about attacks occurring in the United States and the extent to which group dynamics might function similarly or differently when comparing at-home to abroad attacks. What has been documented provides evidence that there is a significant threat, that it is a constantly evolving threat, and that extremists of different ideologies are involved in a significant number of violent and financial crimes. Similarly, although there have been some lessons learned about how to best respond to such terrorism, there is much that is unknown and needs to be discovered. The need for additional research examining the etiology of homegrown terrorism is critical to understand the successes and failures of different types of responses.

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