Domestic Terrorism

Byman and Shapiro on Returning Foreign Fighters

By Benjamin Wittes
Tuesday, January 13, 2015, 6:44 AM

My Brookings colleagues Daniel Byman, Lawfare's Foreign Policy Editor, and Jeremy Shapiro have a new paper out on a very timely subject: returning foreign fighters from Syria and Iraq. Entitled, "Be Afraid. Be A Little Afraid: The Threat of Terrorism from Western Foreign Fighters in Syria and Iraq," it was the subject of an event yesterday at Brookings---the audio of which you can listen to here:

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Here's the executive summary:
On May 24, 2014, a man walked into the Jewish Museum in Brussels and opened fire with a pistol and an AK-47, killing four people in just seconds. This attack was more than just another incident of senseless gun violence. The alleged perpetrator, Mehdi Nemmouche, was a French citizen who had spent the last year fighting Syria. As such, this attack appears to have been the very first instance of spillover of the Syrian civil war into the European Union. For many U.S. and European intelligence officials, it seemed a harbinger. They fear that a wave of terrorism will sweep over Europe, driven by the civil war in Syria and the crisis in Iraq. Despite these fears and the real danger that motivates them, the Syrian and Iraqi foreign fighter threat can easily be exaggerated. Fears about foreign fighters were raised concerning many conflicts, especially after the 2003 U.S. invasion of Iraq; yet for the most part, these conflicts did not produce a surge in terrorism in Europe or the United States. Indeed, in the case of Iraq in particular, returning foreign fighters proved much less of a terrorist threat than originally predicted by security services. Previous cases and the information already emerging from Syria suggest several mitigating effects that reduce---but hardly eliminate---the potential terrorist threat from foreign fighters who have gone to Syria. Mitigating factors include:
  • Many die, blowing themselves up in suicide attacks or perishing quickly in firefights with opposing forces.
  • Many never return home, but continue fighting in the conflict zone or at the next battle for jihad.
  • Many of those who go quickly become disillusioned, and even many of those who return often are not violent.
  • Others are arrested or disrupted by intelligence services. Indeed, becoming a foreign fighter---particularly with today’s heavy use of social media---makes a terrorist far more likely to come to the attention of security services.
The danger posed by returning foreign fighters is real, but American and European security services have tools that they have successfully deployed in the past to mitigate the threat. These tools will have to be adapted to the new context in Syria and Iraq, but they will remain useful and effective. Experience thus far validates both perspectives on the nature of the threat. The Nemmouche attack demonstrates the danger, but European security services have also disrupted five plots with possible links to Syrian foreign fighters to date, in locales ranging from Kosovo to the United Kingdom. Even the one successful attack in Brussels demonstrates why Syria’s foreign fighters are less of a danger than is often supposed. Nemmouche was known to French counterterrorism officials who had placed him under surveillance after his return from Syria, specifically because he had been in Syria. He escaped greater notice probably because he acted alone, but that also limited his impact. And while Nemmouche appears to have picked up some weapons skills in Syria, he apparently had no idea how to operate as an undercover terrorist in Europe. He failed to get rid of the guns he used in the attack and boarded a bus on a well-known cannabis smuggling route, leading to his capture. Many security officials do not find Nemmouche’s shortcomings very reassuring. Security officials are paid to worry about threats and, despite the mitigating factors, foreign fighters in Iraq and Syria provide ample room for worry. Thousands of Sunni Muslims have gone to fight alongside their fellow Sunnis against the Syrian and Iraqi regimes. (Thousands more Shi’a have gone to fight on the side of those governments. But it is the Sunni foreign fighters from Europe and America, with passports that enable them to go anywhere in Europe or the United States without a visa, who worry Western officials.) The overwhelming majority of foreign fighters who have gone abroad to join the fight in Syria and Iraq have come from the Arab world. But Western Europe’s sixteen million and America’s two million Muslims also feel the pull: the carnage in Syria, the refugee crisis, and the violence between religious communities there have echoed throughout the West. Satellite television and social media bring images of sorrow and slaughter into the homes of Western Muslims every day. All sides increasingly consider the conflict sectarian, pitting Iraq and Syria’s Sunnis against the Iraqi and Syrian regimes and their Shi’a supporters in Syria, Iraq, Iran, and elsewhere. Western security services fear that the foreign fighter threat in Syria and Iraq is different in important ways than past foreign fighter problems. Young European and American Muslims will go off to fight in Syria and Iraq as Sunni idealists but will return as anti-Western terrorists. They see combat experience in the region as a double threat. Many of those who go to war will come back as hardened veterans, steady in the face of danger and skilled in the use of weapons and explosives—ideal terrorist recruiting material. While in the combat zone, they will form networks with other Western Muslims and establish ties to jihadists around the world, making them prone to further radicalization and giving them access to training, weapons, and other resources they might otherwise lack. Charles Farr, director general of the UK’s Office for Security and Counter-Terrorism, claims that “Syria is a very profound game-changer,” while the Netherlands’ national coordinator for security and counterterrorism warns that “these people are not only coming back with radical ideas; they are also traumatised and fully prepared to use violence.” This fear of violence is particularly acute because many of those going to Syria and Iraq are social misfits and “marginalized… juvenile delinquents. It’s often people who were criminals before,” according to French officials. American officials have similar fears. FBI director James Comey stated that “All of us with a memory of the ’80s and ’90s saw the line drawn from Afghanistan in the ’80s and ’90s to Sept. 11.” He then warned: “We see Syria as that, but an order of magnitude worse in a couple of respects. Far more people going there. Far easier to travel to and back from. So, there’s going to be a diaspora out of Syria at some point and we are determined not to let lines be drawn from Syria today to a future 9/11.” Comey also explained that because the European Muslims are from countries whose citizens can travel to the United States without a visa, they are of greater concern, as they can more easily slip through U.S. security. Most importantly, the foreign fighter problem in Iraq and Syria is simply bigger than past cases. Recent reports estimate that between 2,000 and 3,000 foreign fighters from Western countries have traveled to Syria and Iraq as of September 2014, including over 100 Americans; France, Britain, Belgium, and Germany have the largest numbers of citizens in the fight. However, these figures may underestimate the flow of fighters: Syria has many entry points, and Western security services recognize that they often do not know who has gone to fight. As the wars continue, the flow is likely to increase. The problem may prove a long-term one, as the networks and skills formed in Syria and Iraq today are used in the coming years to fight against the next grievance to emerge. One expert compared it to a “ticking time bomb,” and Andrew Parker, director general of MI-5 (Britain’s domestic intelligence service) has affirmed that “A growing proportion of our casework now has some link to Syria.” This paper attempts to understand the foreign fighter threat to the West, both the real dangers it presents and the mitigating factors. The foreign fighter threat---and the mitigating factors---can be pictured as a process from recruitment to fighting abroad to terrorism. But this process is not inexorable, and there are many possible exits and roadblocks on the route to terrorism. Indeed, the vast majority of individuals do not pass through the entire process. Most move off the road to terrorism, exiting at different stages in the process. Each conflict has its own dynamics that influence the likelihood that a given individual will travel all the way through the process to terrorism. Using this framework, our policy recommendations focus on trying to identify opportunities to encourage potentially dangerous individuals to take more peaceful paths and to help determine which individuals deserve arrest, visa denial, preventive detention, or other forms of disruption. Steps include increasing community engagement efforts to dissuade potential fighters from going to Syria or Iraq; working more with Turkey to disrupt transit routes; improving de-radicalization programs to “turn” returning fighters into intelligence sources or make them less likely to engage in violence; and avoiding blanket prosecution efforts. Most important, security services must be properly resourced and organized to handle the potential danger. Taken together, these measures will reduce the likelihood that any one individual will either want to move or succeed in moving all the way down the path from concerned observer to foreign fighter to terrorist. This paper first lays out the standard schematic view of how and why some foreign fighters become dangerous terrorists, drawing on the Afghanistan experience in the 1980s to illustrate the arguments. The second section discusses why many seasoned observers believe the Syria conflict is likely to be particularly dangerous. In the third section, we examine why terrorism in Europe and the United States was less than expected from previous jihads such as Iraq, again drawing implications and lessons specific to Syria, as well as examining factors unique to the Syrian conflict itself. The fourth and final section identifies policy implications and recommendations.