What threat do foreign Arab jihadists returning from the war in Syria and Iraq pose to their home states and the broader Arab world? Foreign fighters come back as hardened veterans, steady in the face of danger and skilled in the use of weapons and explosives. While in the conflict zone, they will form networks with other radicals, embrace techniques like suicide bombings and beheadings, and establish ties to jihadists around the world. Different countries have different mitigating factors that limit the danger. The presence or absence of strong and focused security services is particularly important. Returnees' ambition, regional focus, lack of discipline, and brutality often mean they create more enemies than they vanquish and anger local populations. Most terrorism will be locally and regionally focused, with international terrorism probably less of a priority. Area regimes can reduce the risk of bleedout by hindering the travel of volunteers and constraining their ability to organize, stressing the internecine nature of the violence in the Sunni Muslim community, and developing effective de-radicalization programs. Regional and international cooperation to monitor and disrupt travel is also valuable. Many regimes, however, are also likely to take advantage of the jihadists' presence to gain more support from the United States, delay democratic reforms, and crackdown on non-jihadist opposition. Improving intelligence sharing and offensive counterintelligence is important, and the United States can play an important facilitating role.
Byman, Daniel. 2015. "The Homecomings: What Happens When Arab Foreign Fighters in Iraq and Syria Return?" Studies in Conflict & Terrorism 38 (May): 581-602. http://www.tandfonline.com/doi/abs/10.1080/1057610X.2015.1031556