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Domestic Radicalization Research Yields Possible Keys to Identifying Extremists on the Path to Terrorism

Multiple research initiatives sponsored by the National Institute of Justice under its Domestic Radicalization to Terrorism program are illuminating warning signs that may emerge when domestic extremists are preparing for possible terrorist acts.
Date Published
June 25, 2018

An array of new research on domestic radicalization is yielding a more clearly articulated portrait of terrorists in the making – knowledge that can better equip practitioners and community members to potentially spot and divert or stop extremists before they engage in acts of terror.

Two new papers[1] by social scientist Allison G. Smith summarize and synthesize key findings to date from eight NIJ-funded terrorism research projects involving leading U.S. and foreign terrorism researchers. Smith's pair of papers largely cover the same research projects, but one paper is organized around risk factors and indicators associated with radicalization to terrorism, whereas the other is focused on how that radicalization occurs – processes that facilitate the extremist's emergence as terrorist as well as models and frameworks that help explain that deadly transition.

The research on how and why extremists turn into terrorists highlights the social nature of radicalization, as individuals strengthen ties to those who support terrorism while isolating themselves from those who do not, the paper on radicalization processes reports. "This suggests that dramatic changes in the people with whom an individual associates, or increasing insularity among existing groups of friends, may be causes for concern," that paper states.

The risk-factor paper also spotlights an opportunity for community members to act when communications from lone-actor extremists may signal terrorist intent. "Specifically, lone actors who engaged or attempted to engage in terrorism tended to broadcast their intent to do so, as well as convey information about their grievances, extremist ideologies or desire to hurt others," Smith wrote. But because there was no comparison group in the underlying research for that lone-actor terrorist finding, Smith cautioned that one could not rule out nonterrorists engaging in similar communications.

Depending on the individual case, prevention and intervention may be advanced by addressing individuals' terrorist beliefs, enhancing employment or educational prospects, treating mental health problems, or helping individuals develop positive relationships with nonextremists, according to the risk-factor paper. Underlying research distilled a total of 16 distinct "potential risk factors" associated with engaging or attempting to engage in terrorism, among both group-based terrorists and lone actors, with the following factors common to both groups:

  • Having a criminal history.
  • Having mental health issues (or receiving a diagnosis of schizophrenia or delusional disorder).
  • Being unemployed.
  • Being single.
  • Being a loner (or socially isolated).
  • Having military experience.

Smith also calls the finding that military experience is a risk factor "unexpected," but possibly related to the ability or perceived ability to carry out an attack. Two reported potential indicators relate to preparing for attacks: attending more extremist group meetings and stockpiling weapons.

The findings that mental health issues and criminal history are terrorism risk factors "seem striking," Smith writes, to the extent that they challenge the orthodoxy that terrorists are motivated by ideology, not criminal purpose. On the other hand, the author notes that other studies have emphasized the psychological normality of terrorists.

Collectively, the new research reports are the fruit of NIJ's Domestic Radicalization to Terrorism program, created to sponsor research on how radicalization to terrorism occurs in the United States in order to support prevention and intervention.

Smith's survey paper on how the radicalization process works notes that although the research describes possible characteristics of those who engage in terrorism, it is not clear whether those traits differ from those of individuals who do not engage in terrorism. Thus, "[t]he findings provide information on the process of radicalization to violence, but they cannot identify the causes of terrorism."

Another caveat: Research techniques were used to evaluate the relationship between each risk factor and engaging or attempting to engage in terrorism, but the impact of various combinations of risk factors was not assessed.

About This Article

This articles provides a short summary of two papers by social scientist Allison G. Smith, How Radicalization to Terrorism Occurs in the United States: What Research Sponsored by the National Institute of Justice Tells Us (pdf, 27 pages) and Risk Factors and Indicators Associated With Radicalization to Terrorism in the United States: What Research Sponsored by the National Institute of Justice Tells Us (pdf, 34 pages).

These papers were commissioned by the National Institute of Justice under contract number 2010F_10097.

Research from NIJ's Domestic Radicalization to Terrorism portfolio discussed in these papers include:

  • "Empirical Assessment of Domestic Radicalization Project" (NIJ Award 2012-ZA-BX-0005).
  • "Identity and Framing Theory, Precursor Activity, and the Radicalization Process" (NIJ Award 2012-ZA-BX-0003).
  • "Sequencing Terrorists' Precursor Behaviors: A Crime Specific Analysis" (NIJ Award 2013-ZA-BX-0001).
  • "Lone Wolf Terrorism in America: Using Knowledge of Radicalization Pathways to Forge Prevention Strategies" (NIJ Award 2012-ZA-BX-0001).
  • "Across the Universe? A Comparative Analysis of Violent Behavior and Radicalization Across Three Offender Types With Implications for Criminal Justice Training and Education" (NIJ Award 2013-ZA-BX-0002).
  • "The Role of Social Networks in the Evolution of Al Qaeda-inspired Violent Extremism in the United States, 1993-2013" (NIJ Award 2012-ZA-BX-0006).
  • "Prisoner Recollections: The Role of Internet Use and Real-Life Networks in the Early Radicalization of Islamist Terrorist Offenders" (NIJ Award 2013-ZA-BX-0005).

Date Published: June 25, 2018