Assad’s fall lays the ground for wider peace—if the US can seize the moment

The epochal collapse of the Assad government, along with much of the Iranian regional network, has opened the door to a more peaceful Middle East, but has also created risks. The current administration must handle these with urgency, not leave them to its successor.

High among those challenges is helping America’s effective counter-ISIS partner, the Kurdish-led Syrian Democratic Forces, or SDF, emerge as a political representative of the Syrian Kurds. This requires a shift away from its roots in the Turkish separatist group PKK, and from its status as “state and militia within a state.” Washington has a moral duty and geopolitical interest to ensure that the Kurds are not crushed militarily, and that the fight against ISIS not lag. But the U.S. must not indefinitely prop up a Kurdish statelet inside Syria as a perpetual counter-terrorism partner or “great game” Levantine pawn, in the face of resistance from the new Syrian national government and the regional king-maker, Turkiye.

It is important that this transition be gradual. The SDF remains irreplaceable in the fight against ISIS remnants, and the new Syrian state is currently unable to govern the millions of Syrians now under Kurdish rule.

But the transition must also be inevitable. Turkiye has long viewed the SDF, given its undeniable ties to the PKK, as a serious national-security threat. Beginning in 2016, Ankara launched a series of armed incursions to stem SDF expansion along the border, ceasing only when Washington and Ankara finally hammered out a ceasefire for northeastern Syria in October 2019. U.S. sponsorship of the SDF has also damaged U.S.-Turkish relations.

The U.S.-SDF alliance has endured, despite Turkish distrust of U.S. intentions and calls to withdraw U.S. troops in the Trump and Biden administrations, on three pillars. First, the inability of the Assad regime to effectively and humanely replace SDF governance in the northeast. Second, the U.S. military presence keeps Iran, Russia, and the Assad regime from accessing the northeast (and the south at Tanf), denying them a strategic advantage inimical to Turkish and U.S. interests. Third, ISIS remains resilient south of the Euphrates, where Assad regime operations repeatedly failed.

But with Assad’s sudden collapse, tension soared between the Kurdish forces west of the Euphrates (most are technically not part of the SDF, but of its core element, the Syrian Kurdish PKK offshoot called YPG or the Peoples’ Defense Units), and the opposition Syrian National Army forces backed by Ankara. The SNA swept into Tal Rifaat and Manbij, two Arab-majority areas seized during the civil war by the YPG. YPG withdrawals were negotiated, with help from the United States. But the SNA and Turkish forces are now poised to attack east across the Euphrates into the Kurds’ homeland around Kobane. The could spark massive fighting that would also violate the 2019 Turkish-U.S. agreement and could embroil U.S. advisors on the ground. 

U.S. officials have signaled their continuing support for the SDF. On Dec. 13, National Security Advisor Jake Sullivan called it “deep and resolute,” reinforcing Secretary of State Antony Blinken’s talks in Ankara with President Recip Tayyip Erdogan and Foreign Minister Hakan Fidan. The result for the moment is a temporary ceasefire around Manbij and no new Turkish moves into northeast Syria. But after the Dec. 12 meeting, Fidan reiterated that Turkey wants to see the YPG sever overt ties with the PKK, and disarm.  That’s a longer-term wish-list whose details can be negotiated, but the Turks are serious. The HTS-led provisional government in Damascus also appears interested in establishing control in the northeast, and shutting down private armies.

But all three pillars of the U.S.-SDF alliance are crumbling with the Assad regime. The caretaker Syrian government with its HTS and other forces will eventually be able, with international assistance, to take on ISIS remnants themselves. It will also eventually establish governance throughout Syria, including the northeast, as welcomed in the multinational Dec. 13 Aqaba Statement. And the secondary mission of the U.S. presence, to stymie Iran and proxies and Russia, has been largely achieved with Assad’s fall. Furthermore, the U.S. military presence is on borrowed time, with a new administration skeptical of such deployments, and the announced closure of the rear base in Iraq for troops in Syria by the end of 2026.  

Administration actions this past week on Syria have been on target, reaching out to the HTS-led government and laying out reasonable conditions for cooperation, while freezing for now conflict between Turkiye and the SDF. The hat trick is, to continue temporarily engagement with the SDF against ISIS, while preparing for the inevitable major transition. The SDF has already taken some steps under Turkish pressure and U.S. urging: withdrawing forces from the Turkish border in some areas and promising to expel immediately non-Syrian PKK members.

Further steps in coordination with the U.S. are needed. Experience shows that unless Washington signals there is no alternative, the SDF and its PKK sponsors will opt for the “state within a state” and assume that the U.S. will keep protecting it. The SDF thus should negotiate with the caretaker Damascus government on the latter’s assuming functions in the northeast, first in Arab areas, and on “state sovereignty” missions such as transportation, border security (another Turkish demand), and oilfield management, with a plan for eventual normal national control, as well as operations against ISIS. With U.S. help, the SDF should resurrect the buffer-zone concept along the Turkish border agreed between Ankara, Washington, and the SDF in 2019, including joint U.S.-Turkish patrols, until the central government can assume border control. The SDF should open channels to Ankara and lay out a step-by-step plan for its demobilization and transformation into a political party without overt institutional links to the PKK, similar to the largely Kurdish Peoples’ Equality and Democratic Party in Turkey.

Kurdish leaders appear willing to consider all this. But Washington will likely be tempted to stick indefinitely with the Kurds, out of well-earned affection for the SDF, understandable distrust of HTS and Turkiye, desire to fight ISIS and other terror groups, or a romantic vision of the Kurds as a permanent U.S. partner in the Levant “great game.”  

These are all recipes for failure, in Syria and the region. To counter them, the next administration should—while contining the above initiatives—announce an eventual withdrawal of all forces from Syria, based on conditions, but no later than December 2026, absent a new agreement with Damascus. 

James Jeffrey is chair of the Middle East program at the Wilson Center; a former U.S. ambassador to Turkey, Iraq, and Albania; and former Special Envoy to the Global Coalition To Defeat ISIS, and Syria chief of mission.