The Threat of Foreign Fighters Returning Home

There is considerable outrage in the press over the photo of a young boy holding a severed head in Syria. Part of what is fueling the story is the reports that the boy is the son of an Australian Jihadist who traveled to Syria to join the fight. Thus, the story feeds into concerns about so-called "foreign fighters."

Beyond concerns for the children in the immediate case, there are concerns that foreign fighters will return home to plot terror attacks. Indeed, US Secretary of State Kerry, who is currently in Australia, called for talks on how to handle foreign fighters.

However, research by Thomas Hegghammer suggests that these concerns may be overblown. In a Monkey Cage post from September 2013, Hegghammer summarizes the results of a paper he published in the APSR, Hegghammer collected data on foreign fighters and he summarized his findings as follows:

My article tries to answer these questions by looking at where Western jihadists have chosen to fight over the years and why. I rely on open-source data, including a new dataset on jihadi plots in the West from 1990-2010 and data on foreign fighter flows. My five main findings are:

• Foreign fighting is by far the most common activity. Foreign fighters outnumber domestic attackers by at least 3 to 1 (over 900 vs. 300 individuals over 20 years).

• Western jihadists seem to prefer foreign fighting for normative reasons. They heed religious authorities who consider fighting in warzones more legitimate than killing civilians in Western cities.

• Most foreign fighters appear not to leave with the intention to train for a domestic operation.  However, a minority do acquire this motivation after their departure.

• Most foreign fighters never return for domestic plots. In my data, at most 1 in 9 foreign fighters came home to roost.

• Those foreign fighters who do return are significantly more effective operatives than non-veterans. They act as entrepreneurs and concoct plots that are twice as likely to kill.