The US and the Kurds in the new Syria

Key Takeaways:

• To address the issue of the YPG/SDF, Washington needs to employ a multi-faceted strategy that balances counterterrorism objectives with the need to maintain strong bilateral relations with Ankara.
• The Biden administration has been clear in its support for the SDF, with its primary threat perception in Syria centered on ISIS. However, Trump’s return raises questions about how long Washington will continue its support.
• If Erdogan manages to convince Trump that a joint force consisting of the Turkish military and Syrian groups loyal to Ankara can take on ISIS and contain the risk of a jihadist resurgence, it is likely that the SDF will lose US support.
• The new Syrian administration will find itself torn between Washington’s and Ankara’s conflicting priorities. While Washington will hold leverage on critical issues, such as lifting sanctions, the new regime in Damascus may lean more toward Turkiye’s priorities.

Now that the Assad regime is gone and the Islamist-led government of Hay’at Tahrir al-Sham (HTS) is in charge of Damascus, the fate of ISIS and Syria’s Kurds will greatly impact the nature of the new Syrian regime as well as future Turkish-American relations. The Syrian National Army (SNA), a rebel group supported by Turkiye, is currently confronting the Kurdish-led Syrian Democratic Forces (SDF), a US-backed militia that played a critical role in defeating and containing ISIS.  Ankara sees the SDF as an extension of Turkiye’s outlawed Kurdish Workers’ Party (PKK). While the US also designates the PKK as a terrorist organization, it considers the SDF as a separate entity, thus justifying its continued support to the SDF.

Throughout much of the Syrian civil war, which started in 2011, Kurdish militias prioritized controlling their own territory over fighting Assad.  The US identified them as strategic allies in the fight against ISIS, which captured large swaths of territory in Syria and Iraq in 2014. Washington armed and trained the People’s Defense Units (YPG). After capitalizing on the chaos of Syria’s civil war and battle against ISIS, the SDF took control of 25 per cent to 30 per cent of northeastern Syria, including key oil fields and agricultural areas, granting them substantial leverage in the country’s geopolitical landscape.

Syrian Kurds, who at 2.5 million people make up about 10 per cent of the country’s population, carved out their own territory during the civil war and fear they may wind up worse off under the post-Assad government led by the HTS. In view of the new developments, they fear that the US would cease supporting them. These concerns are heightened by historical precedents where major powers have supported the Kurds for geostrategic purposes only to abandon them once their objectives were met.

US Navigation Between Syrian Kurds and Ankara

Navigating the YPG-PKK issue requires Washington to employ a multifaceted strategy that balances counterterrorism objectives with the imperative of maintaining strong bilateral relations with Turkiye. This involves continuous diplomatic engagement, strategic military cooperation and a nuanced understanding of the regional geopolitical landscape. The recent geopolitical shift in Syria adds new layers of complexity for Washington in terms of whether the YPG/SDF will be able to maintain its arms and autonomous status in a federative-decentralized constitutional framework.

Mazloum Abdi, head of the SDF, says he is prepared to dissolve his group, re-brand its 100,000-strong force and join a new Syrian army led by the post-Assad authorities in Damascus. But first he wants to negotiate rights for the Kurds who account for about 10 per cent of Syria’s population. “We want Syria to be decentralized, based on democratic pluralistic principles, with local councils sharing some of those powers in agreement with the central authority.”

While the US continues to collaborate with Kurdish forces in Syria and acknowledges their contributions to regional security, it stops short of formally endorsing Kurdish autonomy in the emerging Syrian political landscape. The US approach appears to focus on maintaining security and stability, countering ISIS resurgence and managing complex regional relationships rather than advocating for specific political arrangements within Syria. The Biden administration has quickly established dialogue with the HTS and wants to maintain leverage over the new regime in Damascus. A US delegation, led by Assistant Secretary of State for the Middle East Barbara Leaf, met with Ahmad al-Sharaa, the HTS leader.

The new government in Damascus is fully aware that its international legitimacy would be enhanced by Washington’s termination of the designation of the HTS as a Foreign Terrorist Organization and lifting sanctions imposed on Syria in order the start the reconstruction process.

Although the US lifted a bounty offered for the capture of HTS leader al-Sharaa, and the Department of Treasury issued a sanctions relief authorization to allow basic human needs into Syria for a six-month period, the tendency in Washington is to wait and see actions on the ground.  Much will depend on whether and how much common ground can be found with the post-Assad regime.

If the regime were to perpetuate a civil war, establish a Sharia-based Islamist state or fail to protect the rights of women and ethnic minorities, Washington is unlikely to remove the HTS’s terrorist designation. In such a scenario, the HTS would also struggle to secure aid and investment necessary for rebuilding the country and facilitating the return of millions of Syrian refugees from the Middle East and Europe. Additionally, Washington’s consideration for lifting the terrorism designation and sanctions hinge on strategic issues such as making sure that Iran cannot use Syria as a land bridge to support of Hezbollah in Lebanon.

As for Turkiye, its priorities in Syria are twofold:

First, Ankara seeks the recognition of the YPG as an illegitimate entity by the HTS and its dissolution as an armed movement. Turkiye fears self-rule for Kurds in Syria could stoke separatist aspirations among its own, far larger Kurdish population. Turkiye is therefore determined to prevent an offshoot of the PKK – a group it has fought for 40 years – from becoming a dominant authority across its border. Although the SDF does not pose a direct military threat to Turkiye, its success would represent a political defeat for Ankara. Turkiye appears to be open to a future formula that would integrate the Kurdish forces into a Syrian army within the context of a unitary state framework, preserving Syria’s territorial integrity and national unity.

Second, Ankara is anxious to see the return of more than four million Syrian citizens who took refugee status in Turkiye since 2012. Ankara also appears to exploit the willingness of the jailed PKK leader Abdullah Ocalan, who is serving a lifetime sentence, to support disarming the PKK and its Syrian wing, the YPG, in return for a potential amnesty. For Erdogan, the ideal outcome would involve significant progress in repatriating Syrian refugees and the YPG-PKK laying down their arms.

However, whether Mazloum Abdi, the YPG leader, would heed Ocalan’s request for disarmament is far from certain since his Syrian organization maintains operational autonomy from the PKK and views the jailed PKK leader primarily as an honorary figurehead. Abdi has established himself as a charismatic military leader who has demonstrated impressive capabilities in the war against ISIS and has so managed to maintain CENTCOM’s support.

Washington’s Threat Perception: ISIS 

The Biden administration has been clear about its support for the SDF and its prioritization of the ISIS threat. “The single biggest concern I have is the resurgence of ISIS,” US National Security Adviser Jake Sullivan stated on CNN on December 22.  However, the return of President-elect Trump now raises questions about the future of Washington’s support. During his first term, Trump ordered US forces out of northern Syria, leaving the SDF vulnerable to a Turkish incursion. Turkiye, which maintains thousands of troops in northern Syria, has launched several offensives against Kurdish militants over the past decade. Senior US officials, including then-Defense Secretary Jim Mattis, resigned in protest over this decision.

On December 19, the Pentagon disclosed that approximately 2,000 soldiers are stationed in eastern Syria – more than double the previously reported 900 troops. The incoming Trump administration will face an early foreign policy test regarding the continuation of this troop presence in both Syria and Iraq. By September 2025, the US is set to reduce its coalition mission in Iraq, though some troops will remain for ongoing security cooperation. In Syria, US forces continue their mission without a specified end date. As the Assad regime was falling in December, Trump has again indicated his aversion to Washington’s continued presence in Syria. “THE UNITED STATES SHOULD HAVE NOTHING TO DO WITH IT…. DO NOT GET INVOLVED!” he posted in an all-caps blast on X.

It is reasonable to assume that President-elect Trump will be briefed by CENTCOM commanders about the strategic need to retain some troop presence in both Iraq and Syria to ensure that ISIS, which still carries a low-level insurgency, does not turn into a major threat once again.  Because of high-profile terrorist attacks such as the recent one in New Orleans and previous ones in 2024 in Iran, as well as widely publicized foiled plots, much of the global media attention has now again focused on ISIS. “The New Orleans terrorist attack simply confirms what many in the counterterrorism community have been saying for the past year, which is that ISIS remains a stubborn and persistent threat and one which simply isn’t going to fade away,” said Colin Clarke of the Soufan Group, a consultancy that focuses on global security issues.

The Pentagon is deeply concerned that ISIS in Syria has been slowly and patiently rebuilding. Over the past five years, as the group’s power ebbed and flowed in Syria, it has retained a steady presence in the central Badia desert, occasionally showing signs of resurgence. In January 2022, ISIS fighters stormed a prison in al-Hasakah, triggering a 10-day battle in which hundreds of ISIS militants were killed but hundreds were also freed from captivity.

The group still boasts several thousand fighters and will likely use the current chaos to recruit new members, potentially including hardline militants who were part of the broader HTS offensive but who disagree with leader al-Sharaa’s emphasis on moderation, inclusion and pragmatism. Since the fall of the Assad regime, the US military has conducted several bombing raids against ISIS positions in Syria. In the first wave in early December, B-52 bombers, F-15 fighters and A-10 Warthogs attacked 75 ISIS targets, including leaders, operatives and training camps. A week later US airstrikes killed another dozen ISIS fighters, targeting more operatives and training camps. And most recently, separate US and French missile strikes targeted ISIS positions in Syria. On December 26, the US Central Command announced the elimination of ISIS leader Abu Yusuf in Deir ez-Zor province in the latest round of precision strikes against the Islamic State’s leadership echelon.

The most glaring vulnerability today lies in the prison camps and detention centers where hundreds of ISIS fighters are held. About 9,000 ISIS militants remain in these camps and over 40,000 of their family members, including women and children, are being held in deplorable conditions. The camps are guarded by the SDF.

Will Erdogan Convince Trump to Leave Syria?

Despite the presence of ISIS in Syria, Ankara considers the American support for the SDF as unnecessary and holds Washington responsible for supporting a Kurdish terrorist group, violating its pledge to cease collaboration with this Kurdish militia. The US had indeed often tried to appease Turkish anger by portraying the military support for the Kurdish group as “temporary, tactical and transactional.” Given president-elect Trump’s preference for ending this involvement in Syria, it is possible that the Trump administration might leave the bulk of the counter-ISIS fight in Syria to the Turkish military. It is not difficult to imagine Turkish President Recep Tayyip Erdogan convincing Trump that in exchange for withdrawing US troops from Syria, the Turkish military will keep ISIS at bay.

Turkish Foreign Minister Hakan Fidan was the first senior foreign official to travel to Syria to meet with al-Sharaa, confirming what many already knew: Ankara wields the most influence with the HTS and will be the major power player in Syrian politics, shaping what comes next. Fidan said recently, “When you look at this from the perspective of US interests, when you do the math, is Turkiye more important, or is a terrorist group like the PKK important? Mr. Trump sees the math right away.”

The SDF leadership is deeply concerned about the possibility of losing Washington’s support, a prospect they view as existential. If Erdogan manages to convince Trump that a combination of Turkish troops in Syria, Turkish proxies like the Syrian National Army and the HTS itself can take the fight to ISIS and contain the Jihadist resurgence, the SDF will have lost its American support.

Conclusions

Despite such dynamics that favor Ankara, it is premature to conclude that the HTS will be controlled by Turkiye or that the United States will quickly withdraw its troops from Syria. As is often the case with the American political system, Damascus will likely receive mixed messages from Washington, reflecting internal deliberations and a potentially chaotic policy-making process. The Pentagon will most probably convince the White House that a quick American exit will be the wrong decision and offer a two-year process of incremental and conditional withdrawal from Syria. The new Syrian regime’s success in fighting ISIS, the status of the Kurds and other minorities and some basic gender rights based on good governance are likely to be the main American metrics for a full withdrawal.

The HTS will therefor find itself torn between the different priorities of Washington and Ankara. The State Department under the leadership of Marco Rubio and the Pentagon under the pressure of CENTCOM will probably insist on some operational autonomy to the YPG/SDF forces in their fight against ISIS with American military support for most of 2025 as a conditional benchmark for partial withdrawal. If the new Syrian military units prove able to effectively fight ISIS on their own, the US can complete its withdrawal at the end of 2026.

If this phased and conditional American exit becomes the Trump administration’s policy, we are likely to witness a clash of Turkish and American priorities in Syria. The reason is simple: Ankara will pressure al-Shaara to disband the Kurdish militia, end the Kurdish project of autonomy and impose central authority over northeast Syria’s  rich oil, gas and agricultural resources.

The HTS, given its strong relations with Ankara and its natural inclination toward asserting full control over all militias in Syria, may lean toward aligning with Turkiye’s priorities. However, Washington retains significant leverage through critical issues such as the lifting of sanctions and the delisting of the HTS as a terrorist organization. As previously argued, these actions are pivotal for Syria to access foreign aid from international organizations such as the Word Bank, the European Union and the United Nations Development Program (UNDP). More importantly, it will be impossible for the new regime to receive foreign investment as long as sanctions are in place. The United States is also the largest donor of humanitarian assistance to the Syria crisis, allocating more than $17.8 billion since 2012 for humanitarian efforts in Syria and in neighboring states that host Syrian refugees.

Trump, for his part, will be under the pressure of the US Congress where Kurds have strong allies. Senator Lindsey Graham, a Republican from South Carolina, recently issued a stark warning on social media, threatening to push for economic sanctions against Turkiye if it attacked the Kurdish forces. He cautioned that such actions could “set in motion an ISIS jailbreak.” He added: “If Turkiye takes military action against Kurdish forces in Syria, it will jeopardize America’s interests dramatically.”

Similarly, Democratic Senator Chris Van Hollen stressed the importance of maintaining US support for Syria’s Kurds. “We should keep a clear-eyed focus on our national security interests, and at the top of that list is preventing a resurgence of ISIS. It’s going to be especially important that we continue to support our partners, the Syrian Kurds, and make it clear that we will not abandon.”

Adding to this dynamic, Mazloum Abdi, the YPG leader, has been reportedly invited to attend Trump’s inauguration on January 20.

The influential Israeli lobby in Congress is also staunchly pro-Kurdish. Similarly, support for Kurds in Israel cuts across an otherwise polarized political spectrum in a bipartisan way. Even the Israeli left that has been critical of Netanyahu believes the US should support the Kurds and that Israel should also help the Syrian Kurds.

As Haaretz argues: “Israel’s friends in the US Congress can be persuaded to push for a cease-fire or convince the Americans to stay in northern Syria and not forsake the Kurds when Donald Trump becomes president. And a lot more can be done in intelligence, cyberwar and arms.”

Ömer Taşpınar is a Non-Resident Researcher at the Emirates Policy Center (EPC). He is a Professor of Security Studies at the National War College (National Defense University, DC campus), a Senior Fellow at the Brookings Institution.