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Understanding the threat: What data tell us about US foreign fighters

NCJ Number
Date Published
4 pages

This Analytical Brief by the National Consortium for the Study of Terrorism and Responses to Terrorism (START) summarizes data collected by START on U.S. residents who are “foreign fighters,” defined by START as “individuals compelled by ideological or other convictions to join insurgencies and military actions outside their nations of residence.”


This report notes that the week before its publication, Ali Saleh, a 22-year-old resident of Queens, New York, was arrested after making several failed attempts to join the Islamic State. This case is not rare, according to the current report;  over the past 18 months, dozens of individuals, many of whom were influenced by ISIS’ social media propaganda machine, have attempted to travel to Iraq and Syria to join the terrorist group. This led FBI Director James Comey to make a public statement that stopping the flow of fighters to foreign combat zones is among the “highest priorities” for the intelligence community. In attempting to address this issue, START researchers have begun to compile a dataset of U.S.-based foreign fighters that contains information on all phases of this trend, including data on pre-travel, travel, and return to the United States of foreign fighters. Although this project’s data collection is ongoing, the current report presents major findings of this effort to date. The data indicate that since 1980, just over 200 Americans have traveled to join about 35 militant groups in approximately 12 unique foreign conflicts, including the war in Eastern Ukraine; however, there is no persuasive evidence to date that “foreign fighters” returning to the United States after participating in foreign conflicts pose a serious threat to public safety in the United States.


Date Published: January 1, 2015