Photo: Syrian Democratic Forces and U.S. troops are seen during a patrol near Turkish border in Hasakah, Syria November 4, 2018. REUTERS/Rodi Said

Turkey was once the main sponsor of the Syrian opposition’s effort to topple Bashar al Assad. However, beginning in late 2016, Turkish policy has shifted following the Russian defeat of Turkish backed proxies in Aleppo. This change in policy sparked a reassessment of Turkish strategy away from the overthrow of the regime and towards close cooperation with Russia and competition with the United States. Beginning in the summer of 2016, Ankara settled on the pursuit of four closely interrelated goals in Syria: blocking westward expansion of the American backed Syrian Democratic Forces (SDF); frustrating American military operations east of the Euphrates River; working through Russia to ensure that Syria remains a unitary state after the conflict ends; resettling displaced people in Turkish controlled territory in northern Syria.

Turkey’s goals are, quite rationally, built around clear and easy to understand security priorities. The SDF is dominated by the Peoples’ Protection Units (YPG), a Syrian militia linked to the Kurdistan Workers’ Party (PKK), an insurgent group the United States and Turkey list as a terrorist organization.

Additionally, the presence of Syrian refugees inside Turkey is a growing political liability for the ruling Justice and Development Party (AKP) given widespread voter resentment about the cost of providing services for Syrians and demographic changes in Turkish cities. Given the electoral and security dynamics, it is easy to understand why Ankara is eager for refugees to return to areas cleared of the Islamic State and Syrian Kurds. It also explains Turkish investment in Syria is primarily in areas it de-facto controls. Ankara is determined to carve out a safe space with viable services to entice people to return home.

Finally, Turkey has allied with Russia to ensure that it plays a significant role in deciding the future of the Syrian state, and to make sure that the United States does not outflank Ankara and reach an agreement to grant some semblance of local autonomy for SDF-allied forces east of the Euphrates river.

To understand Turkish actions in Syria and analyze how to manage the US-Turkish relationship, it is important to accept reality: The United States and Turkey do not share any interests in Syria. Quite the opposite. The two NATO allies are competing actors. However, that does not mean that the bilateral relationship has to implode, or that two sides cannot find ways to cooperate to lessen tensions. To find common ground, it is important for the United States to first answer an unanswered question: What does it want from Turkey in Syria? And, after answering that, devise a set of “hard asks” of Turkey and signal consequences for instances where Turkish action undermines American priorities.

An Open-Ended Commitment: American Goals and the Turkish Response

The Trump administration—after a period of uncertainty sparked by the President’s announcement to withdraw American forces—has settled on a policy of “strategic patience” in Syria. The Trump administration deepened its military relationship with the SDF, received financial assistance from the Kingdom of Saudi Arabia and the United Arab Emirates to underwrite reconstruction efforts in northeast Syria, and pledged support for the UN-led process for peace talks.

Washington has also sought to include Syria in its broader efforts to topple the Iranian regime, arguing that a blow to Iran in Syria would be useful in undermining the Iranian’s government’s hold on power. For this reason, the Trump administration has conditioned support for a peace process on the withdrawal of Iranian commanded forces, and even expressed willingness to work with Russia to secure this outcome.

For the US-Turkish relationship, the main—and most important—fissure remains Washington’s support for the SDF. However, the entirety of the Trump administration’s policy of strategic patience depends on the maintenance of an American military presence in Syria’s northeast, which of course requires strong ties to the SDF. Faced with this obvious fallacy, Washington has sought to find a middle ground, dependent on making concessions to Turkey, while simultaneously reassuring the Syrian Kurds that these moves will mitigate the risk of a Turkish air and ground incursion east of the Euphrates river.

The centerpiece of this impossible balancing act is Manbij, a city on the westernmost outskirts of SDF controlled territory in Aleppo province. The United States and Turkey agreed to the so-called Manbij Roadmap, a conditions based document that called for coordinated, independent patrols; joint patrols; and then the vetting of men and women for leadership positions. The start of the joint American-Turkish patrols fall far short of Ankara’s expectations. The patrols take place once a week, are under the command of an American officer, and (at the time of writing) have taken place along different portions of the forward line of troops. For now, the patrols will not enter the city, an outcome that Ankara has long complained about. The Turkish government has also been explicit in its desire to negotiate separate, “roadmap-style” arrangements for SDF-controlled cities east of the river.

Turkish Priorities

Ankara, as mentioned above, is determined to blunt Kurdish expansionism, and is intent on pushing the YPG off the border. To do so, Ankara uses artillery fire and the ever-present threat of an armed incursion to its advantage.

In parallel, the United States and Turkey have engaged in arduous and difficult negotiations for the rules of engagement governing the joint border patrols. During these talks, Turkish President Recep Tayyip Erdogan repeatedly signaled an expansion of Turkish operations east of the river. Just days before joint patrols were scheduled to begin, artillery strikes began, as part of a broader effort to pressure the United States.

Turkish military action is not without purpose. The targeted shelling exacerbates Kurdish-American tensions over the US-Turkish negotiations for Manbij. At the same time, the Turkey issue creates tensions between different agencies in the US government and frustrates the interagency process. US bureaucratic elements advocate for making more concessions to Turkey versus countervailing constituencies that argue in favor of a more transactional and hard line approach with Ankara. Further still, the now routine artillery shelling helps keep the SDF off balance and, in time, could mask a future armed intervention.

For Turkey, these three outcomes—US-Kurdish tensions, US interagency debate, and softening of defenses—are strategically beneficial for Ankara’s long-term ambitions. The United States can counter with military patrols on the Kurdish side of the forward line of troops, but Ankara can probe for weaknesses, and maintains the option to escalate. A small Turkish military incursion to take control of an isolated border village would be easy to carry out and entail little risk for the Turkish military.

As was the case in both Operations Euphrates Shield and Olive Branch, Turkey could drag along elements of the opposition to give a local face to a Turkish operation and use the inherent right of self-defense to justify the operation. Ankara then would follow with a withering information campaign, designed to portray the operation as a success and react to American support for terrorists.

The operation itself would be small, but the consequences would be of tremendous geopolitical consequence. Ankara could then be expected to further pressure the United States for more concessions vis-a-vis the YPG, in line with the Turkish goal of pushing the Syrian Kurds off the Turkish-Syrian border. With the territorial fight against the Islamic State in its final days, Turkey will have more flexibility. For Ankara, the return of a rural, ISIS-led insurgency in the middle Euphrates river valley is simply not as important as the YPG threat, which many in the Turkish national security bureaucracy view as an existential threat to Turkish territorial integrity.

Policy Options: Tackling the Root of the Problem

Faced with these incompatible interests, it is important for the United States to realistically consider its options in Syria. The presence of US forces constrains Turkish military action (albeit only in areas where they are present). The Turkish policy of pressure also depends on American concessions, and therefore Washington receives little strategic pay off from acquiescing to Turkish demands. The Manbij Roadmap, for example, has not stopped the Turkish shelling of territory inside the US-controlled zone of Syria. Instead, the roadmap has demonstrated the value of a hardline Turkish approach and suggested that a similar effort to coerce the United States could result in the realization of Turkish goals, including concessions on Turkish demands for control over key cities the SDF fought ISIS to take control of east of the Euphrates.

This reality should temper expectations that the US and Turkey can cooperate in Syria, either to topple Assad, or to establish a cohesive territorial and economic entity that links Afrin with Deir Ezzor. Turkey is hostile to the Kurds and should not be expected to support any effort to empower the local SDF-backed councils. Instead, Ankara will try and frustrate any such effort. This begs the question about what the United States should do? The answer requires clarity on what the United States wants from Turkey in Syria. Ankara has clear, hard asks (end support for the YPG and push the group off the border) of Washington and uses coercive pressure to realize those goals. Washington, in contrast, does not yet know what it wants from Turkey —and has therefore struggled to devise a clear strategy.

At the most basic level, the US wants Turkey to refrain from lobbing artillery shells into areas where US forces may be present. However, this is not a concrete policy goal and should not be the main goal of US policy. Instead, the US must recognize Turkish objectives (listed above) and try and shape those goals into an outcome that Washington is prepared to live with. This will not be easy, given the two countries’ vastly different threat perceptions. For the United States, Sunni-majority transnational terrorist groups require a military response to deny safe haven, and has driven the rationale and legal justification for the military campaign in Syria. For Turkey, Sunni-majority terrorist groups are treated as a law-enforcement problem, whereas the PKK (and its affiliates) are treated as a military threat. Thus, the expansion of PKK territories and safe-havens should be eradicated.

Given this schism, it important to note that any US-Turkish effort to narrow these differences faces clear, structural impediments. However, Ankara has, at times, shown a willingness to talk to the PKK and to use diplomacy to manage the threat. A return to a Turkish-PKK ceasefire is in the United States’ best interests and the only way to manage the US-Turkish tensions in Syria.

At a minimum, the viability of US goals in Syria require a hard ceasefire line along the Turkish-Syrian border and along the forward line outside Manbij. The United States has, quite reasonably, sought to use the front lines to its diplomatic advantage, and to push for international political talks to help end the conflict. If the United States is committed to this approach, it would behoove US policymakers to ensure that the Turkish-Kurdish front line does not spiral into another sub-conflict. The US military can, of course, deter Turkish action with patrols, but the small number of soldiers cannot be everywhere at once, and will not be in Syria forever. Ankara, therefore, could exploit areas along the forward line of troops, or simply wait out the United States before taking military action.

To freeze the front lines and to mitigate the drivers of instability in northeastern Syria, the United States should consider placing conditions on further cooperation with Turkey along the forward line of troops. Around Manbij, for example, Turkish backed opposition forces routinely shoot at US patrols. The forward line is clearly marked so the shooting is neither accidental nor a result of mistaken identity. Turkish backed groups are fractured and politically unruly, but if Ankara truly speaks for them in negotiations with the United States, the firing should stop. As a first step, a cessation of violations should be a condition towards any forward movement on the vetting of people returning to Manbij.

The same is true for areas east of the Euphrates, where shelling clearly violates the spirit of US-Turkish cooperation. Ankara is certain to claim that its shelling is in self-defense. This creates an obvious point of leverage, whereby the two sides could agree to monitor the border and record violations of a ceasefire. However, these twin aims are still narrow, and do not amount to a strategy that matches ways, end, and means. A more robust approach, geared towards imposing some sort of order in Syria, requires a more ambitious effort to address the broader PKK issue.

With the Syrian civil war continuing, Ankara has clear goals, built around a coherent set of near term interests. Turkish interests have long been delinked from the future of Bashar al-Assad, and are instead designed to frustrate and upset the US relationship with the SDF. Russia, in this context, is a vehicle to realize this goal. The United States, in contrast, has a different set of priorities and policy goals that require working with an actor that Turkey is committed to destroying. This situation is not tenable.

Without a Turkish-PKK ceasefire, the threat of a broader conflict in Syria will remain. It is in the United States’ longer-term interest to mitigate future sources of conflict. To do so, the US could build upon narrow, condition-based agreements in Syria with the YPG (i.e., those linked to the violence directed at US forces around Manbij and the shelling east of the river) to broader American engagement on the PKK-Turkish government conflict.

Ankara is certain to resist any such effort, but that does not mean the United States should not try to shape outcomes in line with its interests. A return to peace talks, or at the very least, a PKK-Turkish government ceasefire that extends to Syria, should be the American “hard ask” of Turkey. This strategy is the only way to seriously tackle the drivers of instability in northeastern Syria and to prevent Kurdish-Turkish escalation. Until then, the US will use American soldiers as human shields to try and manage tensions in a multi-sided civil war.

Aaron Stein is a senior resident fellow at the Rafik Hariri Center for the Middle East. Follow him on Twitter: @AaronStein1.