As the U.S. and Turkey begin clearing Islamic State fighters from Syria’s northwestern border, their ambitious mission raises a new set of troubling questions, chief among them: Who will provide the military muscle to oust the extremists and protect civilians sheltering in the new buffer zone?
The fracturing of Syria’s opposition suggests that the border region could fall quickly under the sway of Syrian rebels linked to Al Qaeda, insurgents nominally opposed to Islamic State but who share much of the group’s radical ideology.
At the same time, Turkey’s determination to defang forces from its own opposition by excluding them from the new border zone could undermine the very fighters — Kurdish rebel units — who until now have been the most effective ground forces battling Islamic State.