The Terrorist Diaspora After the Fall of the Caliphate

Reports from the Middle East's conflict zones contain the positive news of U.S. and allied forces' successes in Syria and Iraq. U.S.-backed forces in Syria have breached the wall around Raqqa's Old City, marking a major advance in the months-long battle to drive the Islamic State out of its self-declared capital. Prime Minister Abadi arrived in Mosul to formally declare victory after Iraqi troops fought back a fierce resistance from the Islamic State, literally fighting meter by meter, to gain control of the city. Looming over news of victory are questions about the road ahead. Jihadi fighters are fleeing to other towns, concealing themselves among locals, and joining affiliates in places like Egypt, Libya, Yemen, Afghanistan, Nigeria, and the Philippines. A New York Times correspondent reported from Mosul that the recovered bodies of ISIS fighters are primarily from the Caucasus, leaving locals to believe that Iraqi fighters have been shaving their beards, blending into the population, and fleeing with groups of refugees. Western Europe, with its access to the United States, has been a particularly concerning source of foreign fighters. Secretary Kelly recently described as many as 10,000 European citizens that went to take part in the region's sectarian struggle. Europe has had to bear the brunt of the so-called Caliphate's collapse. Facing the return of these jihadists, Europe has increased its defenses in many ways, including through increased intelligence collection and sharing, more programs to vet and screen travelers, and enhanced border security. The question is whether these improvements are enough in light of today's grave threat.