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Updates from the Profiles of Individual Radicalization in the United States (PIRUS) Project


Updates from the Profiles of Individual Radicalization in the United States (PIRUS) Project

January 28, 2015Beth Schwartz

This January, START researchers Herbert Tinsley, Michael Jensen and Patrick James published an updated research brief and fact sheet representing new data from the Profiles of Individual Radicalization in the United States (PIRUS) project.

The project, which began in January 2013, is a dataset of Islamist, Far Left and Far Right individuals who have radicalized to violent and non-violent extremism in the United States. Since World War II, radicalization in the U.S. has occurred in several waves:

  • A surge of Far Left extremism dominated the late 1960s and early 1970s
  • The mid-1990s saw a significant increase Far Right extremist activity, particularly following notable events including the Waco siege in 1993 and the Oklahoma City bombing in 1995
  • A wave of primarily Islamist extremists occurred following the 9/11 attacks

Among the highlights from the most recent round of analysis, the PIRUS data suggest that radicalization appears to be a very social phenomenon, regardless of ideology; about half of individuals studied belonged to a tight-knit insular group and only about ten percent of individuals were so-called “loners.” However, loners and individuals who experience a drop in social standing prior to their illegal extremist activity were more likely to use violence, regardless of ideology.

The data also show some interesting findings when it comes to the duration of radicalization. Far Right extremists typically had a longer period of radicalization than Far Left or Islamist extremists. Furthermore, all individuals who had a longer duration of radicalization were less likely to commit an act of violence, suggesting that individuals’ radicalization trajectory is an important component in predicting outcomes.

Finally, the new data show that there is little to no difference in the role of prison in radicalization processes across ideologies, challenging some recent concerns about the radicalization of Muslim inmates in U.S. prisons. The data suggest that prison radicalization is relatively rare among extremists, and that the risk of prison radicalization is roughly equal for Far Right, Far Left, and Islamist extremists.