Last week, Kurdish forces fighting for the Syria-based Democratic Union Party (PYD) wrested control of the border town of Tel Abyad from the Islamic State. The seizure of the town cut off a key supply line to the Islamic State’s de-facto capital in Raqqa and allowed for the unification of two Kurdish controlled cantons, Kobane and Jazira, between which sits Tel Abyad.

The victory came after the Islamic State nearly defeated PYD forces in Kobane last October, before the dramatic increase in coalition air strikes helped turn the tide of the battle. During the Islamic State’s siege of Kobane, the United States set up a conduit for the PYD to provide targeting data to a military planning office in Erbil, which is then relayed to coalition aircraft. The PYD has since relied heavily on U.S. airpower to aid in their advance and eventual capture of IS-held territory.

Neighboring Turkey has shunned the PYD, owing to its close links to the Kurdistan Workers’ Party (PKK) — a U.S., EU, and Turkish-designated terror group that has been waging an on-and-off-again conflict against the Turkish state for more than three decades. Ankara does not differentiate between the two groups and argues that the PYD’s actions in Syria are tantamount to ethnic cleansing, and part of a broader effort to create a PKK-allied state along its longest land border.

The United States has ignored Turkey’s concerns, pointing to the group’s success against the Islamic State and its distance from Islamist rebel groups — most of which Turkey supports — as the reasons for its continued support. American policy has thus helped to create a Kurdish-controlled enclave in Syria that is hostile to Turkish interests, both inside Turkey and throughout areas in northeastern Syria and northwestern Iraq. Further still, the United States has indirectly signaled that it will now protect Kurdish gains, lest it risk the Islamic State overrunning Kurdish forces in an organized counter attack.

This poses a problem for Turkey. Ankara has pursued on-and-off-again peace negotiations with the PKK since 2006. The Justice and Development Party (AKP)-led process was primarily aimed at ending the violence and creating a viable pathway for the PKK to rely on democratic politics to advance its cause, rather than violence. The two sides agreed to a cease-fire in 2013, but the talks eventually stalled after the AKP demanded that the PKK disarm before negotiations advanced to the next stage. The PKK, in contrast, conditioned its disarmament on the AKP taking more steps to grant Kurdish rights in Turkey.

From the outset of the negotiations, the Turkish state had two interrelated goals: end the violence and undermine the PKK’s popular support. The AKP was eager to create a counterweight to the PKK’s brand of Kurdish nationalism — and thus sought to win the political support of Turkey’s pious Kurds. In doing so, the AKP hoped that ending the violence, the reintegration of Kurds in Turkish society, and improved economic conditions in the southeast would eventually render the PKK obsolete and provide an electoral boon for the AKP in the process.

The AKP had some success in marginalizing the PKK. The loosening of cultural restrictions and the improved economic climate in Turkey’s Kurdish-majority southeast did appeal to many pious Kurds. However, during the battle for Kobane, the AKP adopted hostile rhetoric that helped undermine its support in Kurdish majority areas. Ankara’s ongoing hostility toward the PYD continued to turn off Kurdish voters and eventually resulted in the mass defection of support from these former AKP-supporting religious Kurds to the PKK-linked Peoples’ Democratic Party (HDP) — Turkey’s fourth largest political party.

The AKP and HDP used to be natural allies. The two parties worked together closely on the peace process, before disagreements during the campaign resulted in the freezing of the negotiations. The schisms between the two parties have since grown wider, particularly over the Syrian Kurdish issue. The HDP welcomed the fall of Tel Abyad, for example, saying that every PYD victory against the Islamic State is beneficial for regional security. The AKP, in contrast, has blamed the PYD for uprooting Arab and Turkmen villagers and criticized the United States for giving the “terrorist PYD” direct air support.

This schism has raised concerns that the fragile cease-fire could fail and that the PKK and Turkish state could return to conflict. However, this is unlikely in the near term. The change in American attitudes, combined with the favorable media coverage, create an incentive for the PKK to refrain from attacking Turkey. The PKK’s global image has improved dramatically in recent months, with its female brigades winning favorable attention in international media outlets, and being lauded as the only force capable of defeating the Islamic State. This favorable media coverage has reinvigorated efforts to lobby EU and American policymakers to remove the group from their respective lists of terrorist organizations.

The group’s removal from these lists is unthinkable, given the resistance from Turkey, a NATO ally. Nevertheless, the PYD retains an interest in retaining Western support, especially now that it has united its territory in Syria, and will surely be thinking about winning support for democratic autonomy — or outright independence — in a post-Bashar al Assad Syrian state. Turkey will certainly resist these efforts, but for now the United States appears to have concluded that the PYD is a viable fighting force, worthy of direct air support.

The empowerment of the PYD will have domestic and political repercussions for Turkey. The group’s control of territory in Syria will remain a significant concern for Turkish security and foreign policy officials. For now, both sides have an incentive to refrain from escalating the situation. The PYD would lose international credibility, while Turkey could risk being dragged into the Syrian conflict. However, looking beyond the current conflict, Ankara must now contend with the unthinkable: an American-supported PKK allied statelet along its longest land border. These two actors are certain to remain hostile to each other, giving way to a choice: Ankara could reinvigorate the peace process and try to make peace with the PKK, or it could choose to try to eliminate the threat. This choice suggests continued turmoil in Syria — and perhaps an unintended consequence of the American decision to intervene in the Syrian conflict.

Aaron Stein is a Nonresident Fellow with the Rafik Hariri Center for the Middle East, a Doctoral Fellow at the Geneva Center for Security Policy, and an Associate Fellow at the Royal United Services Institute in London.

Photo credit: Defense Imagery