On Oct. 24, shortly after the U.S.-aligned Syrian Democratic Forces declared the “total liberation” of Raqqa, capital of the Islamic State’s self-proclaimed caliphate, Syria’s information minister told the Russian news agency Sputnik that the Syrian government does “not consider any city liberated until the Syrian Arab army enters it and lifts the Syrian flag.” His comment underscored the government’s determination to re-assert its sovereign authority over all Syrian territory, as well as the ambiguous political situation in eastern Syria, where the United States has effectively become the security guarantor for an expanding Kurdish political project.

Over the past several weeks, a growing number of analysts have concluded that President Bashar al-Assad has won Syria’s brutal civil war. Seemingly on the ropes just two years ago, his government has consolidated control over Syria’s populated western spine, restored 24-hour electricity in Damascus, and is now busy courting foreign investment. Meanwhile, the Syrian armed opposition has been abandoned by its main international sponsors, all of whom have ended or dramatically curtailed their material support. As Ben Hubbard of The New York Times recently put it, Assad “looks as though he is here to stay.”

That may be so. But the temptation to over-interpret the latest events on the street or the battlefield has bedeviled policymakers since the Syrian uprising began. The military challenge to Assad’s rule is over, but significant amounts of Syrian territory remain in the hands of others. If Assad has “won” the war, he’s done so at the cost of dismembering his country. This could be no more than a temporary obstacle on an inexorable path towards total victory. But a number of factors — including Russia’s pragmatic approach to ending the war and the United States’ enduring counter-terrorism objectives — suggest that Syria’s de facto partition is a more likely outcome. What might this look like? And is partition something the United States should accept or oppose?

Syria’s Fractured Political Geography

Since 1900, approximately two dozen conflicts ended by either de facto or de jure partition. These range from the loss of sovereign control over small territorial enclaves (e.g., Cyprus in 1964 or Somaliland in 1991) to declarations of sovereignty with full international recognition (e.g., Eritrea and Croatia in 1991, South Sudan in 2011). Joe Biden famously advocated radical decentralization as a solution to sectarian bloodletting in Iraq. More recently, several analysts have proposed a similar approach in Syria.

This reflects deep skepticism that Assad will be able to reunify the country and a recognition of the degree of fragmentation that’s already taken place. A quick glance at any of the open-source maps depicting areas of control in Syria reveals a complex patchwork of colors corresponding to discrete blocs held by the central government, armed opposition groups, Syrian Kurds and their allies, and ISIL. Damascus’ reach into these territories is deeper than many observers realize — for example, the government has continued to pay salaries to civil servants, even in areas outside its control. But over time, these blocs have become increasingly autonomous: Each flies its own flag, operates its own security, administrative, and judicial institutions, and has developed its own educational curricula.

The pattern of Syria’s fragmentation has been shaped by foreign intervention, first by regional powers, and then by Russia and the United States. Rather than retreating to an Alawite enclave along the Syrian coast, Assad’s government has leveraged support from Iran, Hezbollah, and Russia to roll back opposition gains in Hama, Homs, Dar’a, and the Damascus suburbs, and retaken Aleppo, Syria’s largest city.

In the north, Turkey and its Syrian partners have carved out a rectangular patch of territory along the Syrian-Turkish border that is run by armed opposition groups. Though small, this area is now buzzing with Turkish-funded projects to rebuild infrastructure and restore public services, including schools and religious institutions. While the precise objectives of the new Turkish operation in Idlib province remain unclear, it looks like a first step towards establishing a second Turkish-backed buffer zone in northern Syria.

In the south, Jordan has long exercised influence over the armed opposition in Dar’a province. A July ceasefire agreement between the United States, Russia, and Jordan allowed these forces to hold onto their weapons in return for halting attacks against the Syrian government. This arrangement is fragile —opposition forces would be extremely vulnerable were Assad to concentrate his firepower in the south — but for now, at least, the area remains self-governing and resistant to central authority.

Meanwhile, Israel, which until now managed to remain neutral in the civil war, is increasingly looking to create its own buffer zone inside Syria to prevent Iranian and Iranian-backed forces, including Hezbollah, from operating near the Golan Heights.

Finally, in the east, the Syrian Democratic Forces (SDF) — an alliance of Kurdish, Sunni Arab, and other forces established fight ISIL in partnership with the U.S.-led international coalition — now controls a vast and still-expanding triangle of territory bounded by the Turkish and Iraqi borders and the east bank of the Euphrates River. Nominally still under central government authority, in practice this territory is politically autonomous, administered by SDF civilian councils closely linked to the Kurdish Democratic Union Party (PYD) — a fact illustrated by the removal of both Baathist ideology and the current Syrian president from new textbooks introduced north of Raqqa last month.

Of course, fragmentation is not the same as partition. But this fractured map, and the potential for foreign states to continue providing resources and political backing independent of central authority, complicates any effort to reunify the country.

The Strategic Logic of Partition

It is vital to stress that partition is an outcome almost no one wants. Both Russia and the United States continue to insist on Syria’s unity and territorial integrity, principles enshrined in the Geneva Communiqué and nearly a dozen U.N. Security Council resolutions. Turkey, Iraq, and Iran — each of which has a large and restive Kurdish minority of its own — strongly oppose Syria’s partition.

Within Syria itself, partition is not an appealing option either. While Syrian Kurds overwhelmingly support greater political autonomy, this objective is not broadly shared: After six years of war, the vast majority of Syrians are comfortable with a strong central state and want to keep the country intact. A poll conducted by The Day After Project in December 2015 and January 2016 found that 87 percent of respondents in regime-held areas and 76 percent in opposition-held areas opposed instituting a federal system of government — precisely on the grounds that it would be a step towards partition.

These responses point to the success of more than half a century of Baathist state-building and the fact that many Syrians associate partition with the legacy of World War I, which reduced the former Ottoman province of Syria by nearly half. As the late British writer Patrick Seale put it, “[e]very Syrian schoolchild is brought up to hate the Sykes-Picot Agreement of 1916 and the Balfour Declaration of 1917, the two instruments which in Arab eyes carved up and disposed of ‘Natural Syria.’” Within Syria, discussion of partition is interpreted in the light of this imperial history, rather than as a pragmatic approach to resolving the conflict.

Nevertheless, strategic reality is steadily overwhelming principled opposition.

The most important factor here is security. Having intervened to advance competing interests in Syria, a key priority for all the main international actors is to avoid a broader war with one another. Almost immediately after Russia commenced military operations in September 2015, the United States and Russia established a de-confliction channel at the operational level to reduce the risk of an unwanted confrontation in Syrian airspace; increasingly, this channel has been supplemented by senior-level military contacts. At the same time, both governments have tried assiduously not to demarcate fixed lines on a map that could harden over time. Instead, they have relied on time-delimited “ops boxes” and, more recently, a “soft” line of separation running along the Euphrates River.

These temporary arrangements are unlikely to last, because the shrinking size of the battlefield has exacerbated, not reduced, the risk of an unintended confrontation. With battle lines largely static in western Syria, the east has become the primary theater for making new territorial gains. Deir al-Zour province, where U.S. and Russian-backed forces are now converging, contains approximately half of Syria’s oil deposits and provides access to the strategic border crossing at Abu Kamal. A Russian strike on SDF fighters in mid-September and the subsequent movement by government and pro-government forces across the Euphrates clearly illustrated the risks of a clash in the east.

This is a race for territory: the fight is no longer over Syria as a whole, but for where the lines dividing it will be drawn. To avoid escalation, the United States and Russia will be forced either to accept fixed, agreed lines of separation between their respective partners on the ground, or to stand idly by while these partners fight it out. The latter would badly damage U.S. credibility and leave the United States without a viable counter-terrorism partner in Syria. Indeed, U.S. officials have repeatedly made clear that, while they seek to avoid a confrontation, the United States will not hesitate to defend partner forces from any threat. Once lines are drawn, the fiction of Syria’s unity and territorial integrity becomes much harder to sustain.

A similar process is taking place in western Syria, where Russian-led talks in Astana have established a framework for de-escalation based on the separation of government and opposition armed groups, with the latter continuing to exercise authority in the territory under their control. Talks in September reportedly reached agreement to establish a fourth de-escalation zone in Idlib province, setting the stage for the deployment of Turkish and Russian military observers. From the beginning, the intent of these zones has been to separate the warring parties and stop the fighting — with the hope that the resulting divisions will be resolved as part of a comprehensive national political settlement. But with the Geneva peace process effectively moribund, and Russian reconciliation efforts being challenged, it’s not clear when such a settlement will come about.

While the Syrian government’s participation in the de-escalation deals is cynical at best, Russia’s is pragmatic. By bringing down the violence, Moscow is able to achieve its primary strategic objectives — keeping Assad in power and enhancing its own influence — while avoiding the significant risks and costs associated with a more ambitious effort at national reconquest. And the trade-offs involved in this approach are perfectly clear to Moscow: as the director general of the Russian International Affairs Council, Andrey Kortunov, recently explained, “De-escalation zones are not about a political settlement; they are about military tactics.” Kortunov went on to acknowledge that the zones “might eventually lead to a de facto soft partition of the country.”

Of course, Assad has repeatedly promised to reclaim all of Syria. But he doesn’t have the financial and military resources to do so, even with continuing support from Iran and its proxies. It is certainly conceivable that the Syrian government could pick these zones off one by one through a mix of diplomacy and force — for example, by defeating the opposition in southern Syria, reaching a political accommodation with the SDF and its Kurdish benefactors in the east, and offering Ankara sufficient incentives to permanently withdraw Turkish forces in the north. None of this is assured, however, and it would in any case take months, if not years, to bring about.

What Should the United States Do?

Much of the recent debate has focused on whether the United States should maintain a military presence in eastern Syria to continue applying pressure on ISIL. This is a critical question for U.S. national security, but examined in isolation — that is, as a tactical counter-terrorism matter — it fails to place U.S. military posture within a broader strategy to resolve or at least stabilize Syria’s civil war.

In at least one respect, this is a problem of Washington’s own making.

Over the summer of 2014, the Obama administration made a deliberate decision to keep the campaign against ISIL separate from the broader Syrian civil war. In the wake of ISIL’s seizure of Mosul, opinion clustered around two options. One was to redouble U.S. efforts to press Assad to step aside, allowing the United States to partner with the new government and its Sunni Arab supporters to fight ISIL. The other was to explore partnering with Assad and his forces. The first option showed little understanding of the capabilities of transitional governments; the second would have allied the United States with a murderous regime that lacked legitimacy.

Faced with these unappealing options, the administration developed a third: to cultivate entirely new partners, drawn from among the many Syrians who shared Washington’s more narrowly defined objective of defeating ISIL. This approach evolved into cooperation with Kurdish forces who had proven their mettle in Kobane; ultimately, it grew into a partnership involving the deployment of U.S. Special Operations Forces inside Syria and, under President Donald Trump, the provision of weapons, ammunition, and heavy equipment. As a strategy to defeat ISIL, this approach has proven remarkably successful, as vividly illustrated by the SDF’s seizure of Raqqa earlier this month.

Far less clear are the political implications.

Perhaps inadvertently, the United States’ partnership with the SDF has fueled Kurdish political ambitions and created a permissive environment for experimentation with self-government. Throughout the war, the PYD — the animating political force within the SDF — has maintained an ambiguous relationship with the Syrian government, leaving open the possibility that the SDF might transfer Arab territory taken from ISIL to the central government and more generally submit to central authority in return for greater autonomy within a federal state. So long as the SDF continues to enjoy robust U.S. military support, however, that’s probably not a step the group needs to take. And the PYD almost certainly will try to keep the United States close as a hedge against a potential reconciliation between Damascus and Ankara — an outcome that would expose them to simultaneous attack by two superior military powers.

How should the United States navigate this relationship?

One option, of course, is simply to muddle through, as both the Obama and Trump administrations have done up to this point. This would entail maintaining a public commitment to Syrian unity and territorial integrity, while in practice accepting (if not encouraging) the SDF’s political project as the necessary cost of keeping a limited number of U.S. forces in Syria to combat the ongoing ISIL insurgency.

The problem is that this places the United States squarely in the middle of any future conflict between the Syrian government and the SDF. It also deepens Syria’s fragmentation and increases the likelihood of partition. Rather than helping resolve divisions exposed by the war, partition would reify them, setting the stage for a relapse into violence. In the east, the United States ultimately could find itself contending not only with ISIL, but also with attacks by Syrian government and Iranian-backed forces who are committed to driving U.S. forces out of Syria. There is also the potential for a Sunni Arab revolt against Kurdish domination — either in partnership with or separate from ISIL. And partition would greatly exacerbate tensions both between the United States and Turkey, and in neighboring Iraq.

Alternatively, the United States could embrace a partition strategy and work to mitigate the risks. This would mean dramatically increasing military, stabilization, and other assistance to the SDF, while building diplomatic support for the position that Syria’s reunification can only happen after meaningful political change takes place in Damascus. This approach would match the United States’ partnership with the SDF on the ground to a coherent political strategy — one that would be unlikely to succeed in the near term, but could provide leverage in the future. And it would provide a reliable counter-terrorism partner in close proximity to a known set of threats.

Or the United States could try to reverse Syria’s slide towards partition by redoubling (and probably reshaping) diplomatic efforts in Geneva, encouraging the SDF to reconcile with the central government, and recognizing that any comprehensive deal will involve multiple, painful compromises — including learning to live with Assad in place and negotiating any residual presence of U.S. forces with his government.

That’s a decision the Trump administration would be wise to make sooner, rather than later. Either way, it will be years before Syria can be put back together again.

Alexander Bick is Associate Director and Fellow at the Henry A. Kissinger Center for Global Affairs at Johns Hopkins School of Advanced International Studies. From 2014-2016 he served as Director for Syria at the National Security Council.

Image: Kurdishstruggle/Flickr