ARGUMENT: Defeating Foreign FightersCounterterrorism Successes Against Foreign Fighters

As Dan Byman wrote in his book Road Warriors and in a recent spinoff article in Political Science Quarterly,jihadists who travel abroad to fight and train—foreign fighters—can become highly lethal terrorists. This danger has received renewed attention in recent months with the withdrawal of U.S. forces from Afghanistan and the Taliban takeover there. He notes that these events have kindled fears that, as was true in the 1990s, Afghanistan may become a base for international terrorist groups like al-Qaeda and a home for foreign fighters to train and plot.

“Such concerns, however, neglect the tremendous progress the United States and its allies have made in the post-9/11 era in combating the foreign fighter scourge and limiting the danger they pose to the United States, Canada and Europe,” Byman writes in Lawfare, adding:.

Still, foreign fighters remain a powerful jihadist force worth understanding. Foreign fighters orchestrated and conducted many of the most important jihadist attacks in the past 25 years. Foreign fighters helped plot and organize the 1998 al-Qaeda attacks on two U.S. embassies in Africa that killed 224 people, al-Qaeda bombings of transportation targets in Spain in 2004 that left 191 people dead and in London in 2005 where 52 innocents died, the bombings and shootings in Paris by the Islamic State in 2015 that killed 130 people, and, of course, the 9/11 attacks, in which almost 3,000 people perished. 

As horrific as this list is, foreign fighters often play even more lethal roles outside of their involvement in terror attacks. Their stature and zealotry enables them to better incubate new insurgent groups and radicalize existing ones. This, in turn, worsens existing civil wars and makes them more likely to spread to neighboring countries. These conflicts plague many Muslim-majority countries, with hundreds of thousands dead in Syria, Yemen and other states where jihadist groups have a significant presence.

After militants return from time abroad, they are often far more dangerous. Research by the scholar Thomas Hegghammer found that plots involving foreign fighters are more likely to succeed than those without foreign fighters—and are more lethal when they do succeed. Often, the fighters receive specific training on how to build a bomb, hide from an intelligence service or otherwise successfully plot a terrorist attack. Even when this training is lacking, time in a war zone often makes these fighters more dedicated and steady while plotting an attack. Terrorist groups like al-Qaeda and the Islamic State try to indoctrinate recruits, taking individuals with specific grievances such as the Syrian civil war and introducing them to a more global, and more anti-Western, agenda. Finally, individuals return and are more networked, better able to work with like-minded individuals, some of whom are still overseas, to conduct attacks.

The post-9/11 era overall saw a decline in the role of foreign fighters with regard to successful terrorist attacks. Byman writes that no single policy explains why foreign fighters have become less of a threat to the West. Rather, different policies at different stages provide limited protection in isolation, but the combined effort is highly effective.

He concludes:

Fighting this danger involves an overlapping, but at times different, counterterrorism tool set. As with foreign fighters, good relations with Muslim communities are vital, as they are more likely to know any dangerous elements in their midst. Successfully combating inspired terrorism requires working more effectively with social media companies, and there has been progress on this front. Far more difficult is discrediting the overall jihadist narrative that proclaims the West as an enemy and the United States as a cruel oppressor of Muslims—a narrative that, despite years of U.S. efforts, remains robust.