As Washington considers its next steps in northern Syria, it will need to weigh the geostrategic consequences of backing local Kurdish forces whose objectives may align or conflict with those of Russia, Iran, and various other actors.

In July 2012, as Syria's war intensified, the Assad regime largely pulled out of Kurdish-majority areas in the north. To fill the vacuum, the Syrian Kurdish Democratic Union Party (PYD) and its militia, the People's Defense Units (YPG), took control of these areas, marginalizing other Kurdish factions. They eventually established Rojava, a self-declared autonomous entity stretching across most of the northern frontier. Today, no foreign government recognizes Rojava, and the territories it controls lack the contiguity needed for good governance and economic viability. Nevertheless, the PYD seeks to boost its de facto autonomy.

What are the prospects for Rojava? The following analysis looks at the Kurdish zone's ties with neighboring countries and key military actors inside Syria, outlining four potential scenarios for its future.

ALLIES AND ADVERSARIES

The United States sees the YPG as a tactical ally against the Islamic State (IS), but the Kurds also have good ties with Russia, which recently deployed troops to Rojava's westernmost canton of Afrin. Whereas Washington cooperates with the YPG only where IS forces are present, Moscow seems most interested in Rojava's proximity to Turkey, suggesting a more strategic Russian view of the Kurds as an asset against Ankara.

Further complications arise from the fact that the YPG is an offshoot of the Kurdistan Workers Party (PKK), a U.S.-designated terrorist group that has been battling the Turkish government for decades. Ankara is therefore hostile toward Rojava, conducting airstrikes against YPG positions there as recently as April.

In Iraq, the Kurdistan Regional Government (KRG) and its dominant faction, the Kurdistan Democratic Party (KDP), have a similarly hostile view of Rojava, mainly because the YPG has persecuted other Syrian Kurdish factions, including some that are close to the KDP. The Iraqi Kurds also take issue with the YPG's encroachment on their turf; for example, the group recently established the PKK-friendly Sinjar Resistance Units (YBS) among local Yazidis in Iraq's Sinjar Mountains. The KDP's increasingly good ties with Turkey have only strengthened these sentiments, spurring it to restrict the movement of people and goods into and out of Rojava.

In contrast, Iran welcomes Rojava's recent linkage with Shiite-militia-controlled areas in Iraq, viewing the Syrian Kurdish zone as part of a potential land bridge to Hezbollah in southern Lebanon. The Iraqi government, an ally of Iran, shares this favorable disposition toward Rojava, as exemplified by reports that Baghdad has paid the salaries of YBS fighters. Moreover, the PKK's Iranian offshoot, the Party for a Free Life in Kurdistan (PJAK), has ceased hostilities against Tehran since Syria's war got into full swing -- another sign of their converging interests.

As for Bashar al-Assad, Rojava retains tight economic links with the regime-held portion of Syria and has allowed the army to continue controlling a key airport in the middle of PYD territory. Despite the occasional flare-up, this arrangement gives the Kurds a crucial lifeline to the outside world. Elsewhere, Assad's forces have not moved against Rojava; in fact, Sunni Arab rebel groups allege that the YPG and regime elements have coordinated against them.

Given these overlapping layers of conflicting and converging interests, Rojava will likely follow one of four paths going forward -- and Washington may play a role in determining which one depending on its own actions.

TRANSNISTRIA MODEL: RUSSIAN VASSAL STATUS

This is the most plausible scenario for Rojava, and close to its current status. Moldova's breakaway Transnistria region is not recognized by any foreign government but enjoys strong protection from Moscow, including the presence of Russian troops that give the Kremlin leverage in Moldovan politics. Likewise, Rojava enjoys strong protection from powerful outside states, and it gives Moscow leverage to create instability in Turkey.

The PYD will not be satisfied with the Transnistria model indefinitely, however. This arrangement may be practical for now, but it also suggests pariah status in international law and subservience to Russia. The PYD aims for wider support and de jure international recognition of Rojava's autonomy.

KOSOVO MODEL: PARTIAL RECOGNITION

This is Rojava's dream scenario, but also the least plausible. Kosovo broke away from Serbia thanks to a 1999 UN Security Council resolution that allowed U.S. and international troops to be stationed on Kosovar territory, eventually paving the way for a declaration of independence in 2008. It has since gained recognition from 111 of the 193 UN member states -- most notably excluding Russia.

Implementing this model in Rojava would require a complete rupture between Turkish president Recep Tayyip Erdogan and the United States, whose vote would be needed for any Security Council resolution on the matter. To be sure, such a rupture is more possible than ever given the increasingly anti-American posture of Erdogan's base. Yet it still seems unlikely because he needs security ties with Washington to counter Russia.

Whatever the case, U.S.-Turkish ties could face further challenges after the IS "capital" of Raqqa is liberated in Syria. Potential flashpoints include a YPG refusal to return U.S.-supplied heavy weapons following that campaign. The Kurds might also decide to sideline local Arab leaders in Raqqa, instead turning the city over to figures who are friendly with the YPG or Assad -- both undesirable outcomes for Ankara. In that scenario, Erdogan may find himself overwhelmed by the same anti-American forces he has unleashed in Turkish society, with various Islamist and anti-Kurdish constituencies potentially pushing him to downgrade ties with Washington.

Even if Rojava overcomes all of these challenges, it would still need a great deal of outside help to achieve Kosovo-like status, including at least one Security Council resolution, an activist international community to champion its cause in Syria, and foreign troops to protect it from Turkey. Gaining Russian support for this model at the UN would be especially difficult because the Assad regime still wants to retake as much of the country as possible. Moscow is unlikely to pick the Kurds over Damascus if Assad balks at giving the north fuller autonomy.

KRG MODEL: TURKISH PROTECTION

This is nearly the opposite of the Kosovo trajectory, at least in terms of helping rather than hurting Ankara's interests. Since the Iraq war, the KRG has increased its autonomy from the central government, and the KDP has formed good ties with Ankara as a counterbalance against Baghdad. Although Turkey and the PYD's mother organization, the PKK, are currently fighting, it should be remembered that they were holding substantive peace talks as recently as 2015, and that PYD delegations were making regular visits to Ankara. A return to such talks would automatically normalize Turkish relations with the Syrian Kurds, and Rojava investment opportunities for Turkish businesses would further sweeten the deal.

Yet implementing the KRG model would require an end to the fighting between Turkey and the PKK, and both sides currently seem committed to a military victory. The PKK is animated by the YPG's success in capturing Syrian territory and establishing ties with Russia and the United States simultaneously, so it seems uninterested in resuming talks with Ankara. Likewise, Erdogan is already gearing up for parliamentary elections in 2019 by seeking to boost the popularity of his party among Turkish nationalist voters, most of whom likely prefer defeating the PKK on the battlefield to meeting them at the negotiating table.

Accordingly, the KRG model does not seem plausible in the short term, despite being perhaps the best outcome for the United States. In all likelihood, it cannot take shape until after Erdogan secures his electoral victory in two years, and after the deep Turkish hostility toward the PKK wanes somewhat. In the meantime, the presumed YPG-led liberation of Raqqa may further embolden the PKK to continue fighting Turkey.

1975 ALGERIA MODEL: FORCEFUL REINTEGRATION

In the 1970 peace accord between Baghdad and the Kurds, a hard-pressed Saddam Hussein agreed to give them ample autonomy, and he more or less honored that deal for a few years while he consolidated his position in post-coup Iraq. In 1975, however, Iraq and Iran ended their border disputes and signed the Algeria Agreement, leading Tehran to halt its support for Iraqi Kurdish groups. Saddam soon moved to forcefully end Kurdish autonomy, unleashing harsh repression and eventually genocide.

This precedent from a fellow Baathist regime suggests that Assad might tolerate Rojava's autonomy so long as he is weak, but then seek to end it as soon as he can, in line with his frequent pledge to reestablish control over all of Syria. If so, he would find a helping hand from Turkey, which has repeatedly called for him to step down since the war broke out but is even more concerned about countering the YPG and PKK. Even Tehran might give its blessing for the regime to retake Rojava given its own worries about growing Kurdish nationalism inside Iran, where local Kurds have become more restive despite PJAK's ceasefire. And Moscow might acquiesce as well if it decides that closer relations with Assad are more important than its historical ties with the PYD and PKK.

Washington's political will to oppose such a strategy would likely be limited. In that case, the end result would be Assad, Iran, and Russia spinning Rojava's fall as a victory over America, loudly proclaiming that they defeated all those who took U.S. aid, including the PYD/YPG.

Soner Cagaptay is the Beyer Family Fellow and director of the Turkish Research Program at The Washington Institute, and author of The New Sultan: Erdogan and the Crisis of Modern Turkey.