Indeed, Turkish President Recep Tayyip Erdoğan is set to meet with Russian President Vladimir Putin in the coming days, likely further solidifying their own spheres of influence in Syria, without the United States. For the part it can control, the U.S.-led coalition should work with Turkey, Jordan, and Iraq to reinforce their borders and ensure that no escaped ISIS fighters or family members are able to cross. With the small presence remaining at Syria’s al-Tanf Garrison as well as other bases in the region, the U.S. can still use its intelligence assets along the Iraq-Syria, Jordan-Syria, and Turkey-Syria borders to monitor ISIS movements. The U.S. will also need to maintain its battlefield communications channel with Russia, the Syrian government’s ally, to ensure that, when necessary, it has the ability to strike ISIS or extremist targets from Syrian airspace.

President Donald Trump has made clear that Turkey and other countries now bear the responsibility for the detention of ISIS fighters, but with the regime likely coming into the greater northeast at large—not just towns affected by the offensive—it is probable that a mixture of SDF and regime security forces will continue the security of camps and prison facilities. Both will need to keep dangerous ISIS fighters off the battlefield, as well as work to facilitate aid access into encampments—something that will remain difficult as many aid groups are often unwilling to enter regime territory.