President Trump’s decision to withdraw U.S. troops from Syria has reshuffled the cards in the war-torn country. Turkey intends to reshape northern Syria at the expense of Washington’s partners in the fight against the Islamic State. Syrian Kurds, feeling abandoned, are attempting to cut a deal with the Assad regime. Amid uncertainty and realignment, Russia has become the kingmaker. Can the U.S. reassure its allies and partners while containing Russian and Iranian ambitions in Syria and the Middle East?