Participation in the international coalition against Daesh and the rise of foreign fighters

Cind Du Bois, Caroline Buts


The flow of foreign fighters leaving for Iraq and the Syrian Arab Republic has slowed, but they often still pose a serious threat, either by encouraging others toward violence or by directly assisting themselves in a terrorist attack after their return. This article studies the effect of a country’s active involvement in a conflict zone on the flow of foreign fighters. Specifically, we test whether a nation’s participation in the international coalition against Daesh influences its number of foreign fighters. Despite the small sample size resulting from limited official data on foreign fighters, we report several interesting insights for cautious interpretation and only regarding the countries included. Findings from a negative binomial model suggest that a country’s active international role against Daesh also increases the foreign fighters coming from that country. Hence, it is important to keep in mind that the cost of a military intervention can be higher than the cost of the operation itself. Policymakers should also account for the cost of the increased number of foreign fighters and the resulting threat.


Foreign fighters; military support

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