December 9, 2015

TSG IntelBrief: The Murky Challenge of Returning Foreign Fighters

• The average rate of Western foreign fighters who return from Iraq and Syria to their home countries stands at around 20-30%, presenting a significant challenge to security and law enforcement agencies that must assess the threat that these individuals pose

• The United Kingdom has seen an estimated 350 people return from Syria; France, 250 people; Germany, at least 200; Belgium, 118; and the United States, 40

• The motivations for people to return from Syria and Iraq are as individual and personal as the reasons for going in the first place

• As seen in Paris, the risk of known returnees is already a significant challenge; the risk of those who have returned undetected is something altogether more concerning.


Between 27,000 and 31,000 people are estimated to have traveled to Syria and Iraq to join the so-called Islamic State and other like-minded groups, and preventing more foreign fighters from leaving remains an ongoing challenge. Alongside the fighters who have traveled to Syria, there is growing concern around those who decide to return, for reasons benign or otherwise. Further muddying the waters is that returning foreign fighters needs to be broken down into segments: those who have openly returned (or tried to) and those who returned unannounced and undetected, as was the case in the recent Paris attacks.

The known returnees are not a monolithic bloc, and their reasons for returning are as individual as their reasons for traveling to Syria. Based on official numbers, the average rate of people trying to return to Western countries from Syria is between 20%-30%, with some rates jumping even higher. The United Kingdom has seen an estimated 750 of its citizens leave to join the Islamic State in Syria; an estimated 350 of them have returned or attempted to return. Of the estimated 150 people who traveled from the United States, 40 have returned. 1,700 French nationals have gone to Syria, with perhaps 250 returning. Other Western countries experience similar rates.

What to do with returnees is a pressing issue for their respective countries. Much depends on each foreign fighter's reason for joining the group and their actions while in Syria. The process of vetting someone's actions inside the so-called caliphate is challenging at the very least, leaving authorities with little confidence in granting leniency. Still, there is a wide range of legal responses to returning foreign fighters, to include: prison sentences, parole, monitoring, counseling, and the revocation of citizenship. The case-by-case nature of the assessments is challenging, and societies that have experienced—or fear—attacks by returning fighters are not interested in case-by-case approaches.

From the standpoint of preventing others from traveling to Syria, there is no consensus on the role of former foreign fighters. Some advocate a ‘scared straight’ approach, in which returnees are given highly-publicized and lengthy prison sentences as a warning to would-be followers. Still others argue that—similar to efforts to sway young people from gangs and drugs—the use of ‘formers’ who can serve as credible voices is a more effective deterrent. Given the mulititude of reasons prompting people to leave their homes to travel to fight in Syria, both strategies have their benefits and drawbacks, depending on the individual.

The threat of unknown returnees is as challenging as the threat of known ones. Six of the ten men known to have been involved in plotting and executing the Paris attacks had reportedly traveled to Syria. It is extremely concerning that these six men made an undetected roundtrip; were able to re-enter the EU zone; and were able to plan, prepare, and execute a complicated series of attacks, despite the fact that several were well-known extremists before they left for Syria. Of the roughly 70% of Western foreign fighters who have not openly returned, an unknowable percentage might do as the Paris attackers did—even if the majority prefer to stay in Syria or die there. In countries where there is no available data on returnees, the issue is murkier still.


Download The Soufan Group’s updated report on Foreign Fighters here.


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