Few in the United States or Turkey had ever heard of Manbij before the start of the war against the Islamic State. Despite its small size and pre-war obscurity, the Syrian city has become a key point of contention between two NATO allies. After trading indirect threats for months, the United States and Turkey reached agreement in early June on a roadmap to resolve tensions over governance in Manbij.

The dispute over the small Syrian city speaks to a broader issue: The United States is trying to balance its historic relationship with Turkey, a treaty ally, with its alliance with the Syrian Democratic Forces, a Syria-based militia dominated by the Kurdish-majority People’s Protection Units that is committed to fighting the Islamic State and has a presence in Manbij. The United States has steadfastly avoided calling the Syrian Democratic Forces an ally, given the group’s links to the Kurdistan Workers’ Party (PKK), a U.S.-designated terrorist organization. Because the PKK has waged an insurgency inside Turkey since 1984, Turkey views the Syrian Democratic Forces as a long-term security threat, has severely criticized the United States for working with them, and bitterly contests their influence in Manbij.

The text of the Manbij agreement has not been released, but it appears to have two main components. The first is an arrangement between the American and Turkish militaries to conduct “independent but coordinated patrols” that will eventually be integrated and conducted jointly. The second — and far more difficult — step will involve efforts to change the local system of governance, which is now run by a majority Arab council linked to the Syrian Democratic Forces. The joint patrols give the Turkish military a more direct role in providing security around Manbij, whereas previously the two sides faced off across a semicircular front line. Down the road, after patrols become standardized, Turkey hopes to replace elements of the governing council with its own preferred Syrian groups.

Ankara’s goal is to weaken the Syrian Democratic Forces in favor of its own allied non-state actors, active in Northern Aleppo and trained in Turkey. These goals are entirely logical from Turkey’s perspective, but they also raise the specter of intra-Syrian conflict over control of a city that has been cleared of ISIL. This outcome would be at odds with American interests, which have always been narrowly focused on taking territory from ISIL and securing it against infiltration attempts.

The Manbij roadmap appears deceptively simple. Indeed, the coordination of joint patrols between two allied militaries is easy. However, the broader implementation challenge stems from the basic fact that the three parties — the United States, Turkey, and the Syrian Democratic Forces — have vastly divergent interests in Syria, and should be expected to take different approaches to secure them.

In the ground war against Islamic State, America’s goal of sustaining combat operations is, for the moment, aligned with the aims of the Syrian Democratic Forces. At the same time, the United States seeks to appease Turkey and use Manbij as a lever to reset the bilateral relationship. Turkey, for its part, wants to marginalize the Syrian Democratic Forces’ influence, first in Manbij, and then in Kurdish-controlled areas in northeastern Syria.

The United States has taken on the responsibility of managing relations between two hostile actors, both working independently of their patron in Washington to secure their own opposing interests — but both necessary for U.S. interests. This is a version of the classic “patron-client problem,” whereby America’s ability to shape the behavior of weaker states or groups (“clients”) is limited because those clients know they are vitally important to the patron. The question becomes: Does America know what its own interests are, in Manbij and in Syria more broadly?

A fracturing of the partnership between the United States and the Syrian Democratic Forces could undermine stability in northeast Syria, at a time when President Donald Trump has signaled his desire to rapidly draw down combat troops and leave the task of rebuilding to local actors and regional states — a task dependent on the Syrian Democratic Forces. At the same time, the United States also has an interest in maintaining cordial relations with Turkey. Ankara has signaled that a resolution of Manbij is necessary to help reset the troubled bilateral relationship and begin the process of overcoming tensions. And yet, a narrow, Manbij-specific agreement risks sparking tensions between Turkey and the Syrian Kurds, local clashes, and the undermining of local security — to the benefit of Islamic State — while Trump is pushing for a U.S. exit. Both actors will work to exploit grey areas in the roadmap to their benefit, and not necessarily in ways favorable to U.S. interests. Washington needs to acknowledge its lack of leverage, identify its own interests in Syria, align them with the president’s wishes, and then make the roadmap part of a broader set of policy goals, rather than an independent side agreement meant only to assuage the concerns of its NATO ally.

What’s in the Roadmap?

The current stability in Manbij belies the complexity of the situation and the difficult position the Syrian Democratic Forces are in. To prevent a Turkish incursion to oust the Syrian Kurds from Manbij, the Syrian Democratic Forces reached agreement with the Assad regime in March 2017 to deploy a small number of forces along the western outskirts of the territory. To the north of the city, the United States and France have deployed forces, and frequently conduct deterrence patrols to prevent Turkish attack. The Turkish military has a large military base north of Sajur river and is in control of the territory to the west of the city. Allied nonstate militias who depend on Turkey often shoot at American patrols just over the forward line of troops.

Ankara has threatened that an open-ended U.S. commitment to the Syrian Democratic Forces could prompt Turkish military action, resulting in de facto conflict between two NATO allies. In parallel, the Turkish government has worked more closely with Russia to signal discontent and make it known that Ankara has other alliance options. In an extreme example, Turkish President Recep Tayyip Erdogan threatened to kill American soldiers in Manbij. The tactic was effective. American policymakers felt compelled to travel to Ankara to reduce tensions and mend fences. The result was the roadmap and an overt American commitment to compel the Syrian Democratic Forces to make compromises. The agreement, if fully implemented, could reduce tensions with Turkey, but could also prompt the Syrian Democratic Forces to hold American interests at risk or to explore different alliance partners.

As part of the roadmap, the United States conceded that it need to find a modus vivendi with Turkey, but did manage to win agreement from Ankara about the need for implementation to be conditions-based. In practice, this means the roadmap is not beholden to a rigid timeline, and will instead move forward to the next phase once stability is ensured in the previous one. It also means each side has agreed to manage and account for the behavior of their partner force. Turkey’s allied Arab militias will have to stop shooting at American patrols before U.S. and Turkish forces begin joint patrols while, after the patrols start, the United States will have to ensure that the Syrian Democratic Forces don’t shoot at the Turkish military or its allied militias. At the very least, this is a force protection issue that may stress the small number of U.S. combat troops deployed in Syria.

Turkey and the United States also have mismatched expectations about the roadmap’s implementation. Ankara has framed the document as having a specific timeline, while the United States insists implementation will be conditions-based and open-ended, and won’t result in radical changes to local governance. Ankara has also suggested that the “Manbij model” of joint U.S.-Turkish action to alter local governance arrangements should be applied elsewhere in Kurdish-controlled Syria, whereas the United States has indicated the agreement is narrowly focused.

The Patron-Client Problem: Diverging Interests, Diminishing Leverage

America’s two clients have gained “reverse leverage” over their patron. The Syrian Democratic Forces retains leverage over the United States because it is critical for taking and holding Islamic State territory. Ankara, in contrast, can threaten to hold the U.S.-Turkish relationship hostage and deepen relations with an American adversary, like Russia, to force American concessions. The Turkish government could also, once again, ratchet up hostile rhetoric designed to raise questions in Washington about a total break in bilateral relations.

The Syrian Democratic Forces face a particular dilemma here. To remain relevant in the U.S. debate about managing these conflicting alliances, the Syrian Kurds’ only point of influence is their role in combating ISIL. And yet, as the Islamic State threat recedes, the Syrian Democratic Forces become less relevant for U.S. security interests, and therefore less influential in the policy debates in Washington.

The Manbij roadmap is at odds with the security concerns of the Syrian Democratic Forces, and divergent from their broader ambitions in northeast Syria. The Syrian Democratic Forces are committed to turning its military gains against ISIL into some semblance of self-rule, under which it has local administrative control over security and political affairs. Turkey opposes this, so a concession in Manbij could upend the Kurds’ plans. The Kurds are also acutely aware of their vulnerability to external attack from a superior adversary, such as Turkey, and of the American preference to find common cause with that adversary. Thus, the Syrian Democratic Forces should be expected to begin hedging their bets and to explore accommodation with the regime to try and protect their longer-term security interests. In early June, Ilham Ahmed, the co-chair of the Syrian Democratic Council, the group’s political wing, suggested “unconditional talks” with the regime. The two sides have maintained contact throughout the civil conflict, but remain at odds about how to reconcile the Kurds’ demands for governing power in Syria’s northeast with Assad’s longstanding desire to consolidate control in Damascus.

Absent a direct American role in these talks, the Syrian Democratic Forces could reach an agreement with Damascus that affects the presence of U.S. forces in northeastern Syria or U.S. policy in general. Indeed, such a deal would be entirely rational, given their vulnerability to attack and the perceived diminishing commitment from Washington.

Tactics Without Strategy

The composition of Manbij’s local governance is, ultimately, a minor concern for the United States. However, the balancing act raises broader questions about the future American role in Syria and underscores how complicated it has been to manage the politics of civil war.

As the United States works to manage Turkey and the Syrian Democratic Forces despite its reduced leverage, policymakers should be mindful that these hostile actors could pursue policies at odds with America’s goals. The Syrian Democratic Forces should be expected to pursue de-escalatory measures with the regime and try to ensure some semblance of autonomy after the conflict stops. Turkey will likely oppose this outcome and work through the other parties in the conflict — namely, Russia — to try and prevent the empowerment of Kurdish governance in the northeast.

This wheeling and dealing could make life extremely uncomfortable for American forces in Syria and, absent broader reconciliation with the Syrian Kurds, threaten U.S. military efforts in the country indefinitely. This raises a bigger issue: The roadmap was negotiated independent of any broader American plan for Syria. Specifically, U.S. policymakers have yet to reconcile Trump’s announced intention to withdraw U.S. military forces with the ongoing refusal to negotiate with the Syrian regime. Thus, the United States is trying to mollify a treaty ally, Turkey, while simultaneously managing its ground force, the Syrian Democratic Forces, without having settled on a Syria policy or even articulating achievable policy goals in the multi-sided civil war.

In the absence of such a policy, the Manbij roadmap serves simply as a mechanism to engage with Turkey without securing concrete commitments that Ankara will endorse a broader American effort to wind down the conflict. At some point, the United States will have to grapple directly with the divergent interests of its two allies to ensure that its core focus on holding gains against ISIL is maintained. If the Syrian Kurds and Turkish forces clash, ISIL could benefit. The roadmap ignores this, and instead narrowly focuses on mollifying Turkey while simultaneously managing Kurdish expectations.

Now, therefore, the United States needs to identify its own interests and integrate the Manbij roadmap into a clear approach that supports those interests. This interest-focused approach also needs to be matched with Trump’s declared intent to begin withdrawing American combat forces. The United States went to war in Syria with a narrowly defined counter-terrorism interest. The Syrian Democratic Forces were integral for that effort, and will remain the predominant non-state force in Syria’s northeast for the foreseeable future. Turkey is Syria’s most powerful neighbor and has a legitimate interest in undercutting the Syrian Democratic Forces.

The roadmap does not address this core problem, and therefore creates a danger that each U.S. client will take steps to secure its own immediate security interests, which are in contradiction and could easily spiral into direct conflict. For the United States, any such conflict risks the gains made against ISIL and, more generally, would pit a non-state actor that the U.S. army helped train against a NATO ally.

To navigate this minefield, Washington must acknowledge that it cannot achieve maximalist goals in Syria, and instead be pragmatic about what it wants and realistically assess whether those goals are achievable. For example, the United States must seriously plan for the withdrawal of troops, and then reach agreement with the various actors involved in the conflict to ensure that American’s core counter-ISIL goal is realized even as troops begin going home. To do this, in turn, the United States will have to recognize that it must reach some common understanding with Russia about the future of Syria — and about how the Syrian Democratic Forces fit into that future. By doing so, Washington will be better prepared to make hard asks of its two allies in Syria, rather than simply responding to the demands of one (Turkey) at the expense of the other (the Syrian Democratic Forces). Such an approach would not symbolize American weakness, but would instead position Washington to better manage the patron-client problem it is now faced with. Absent a more robust approach, the United States will be left managing two ideologically opposed allies, both of whom are undercutting American interests in Syria.

Aaron Stein is a senior fellow at the Atlantic Council’s Rafik Hariri Center for the Middle East.

Image: Anadolu Agency