A Kurdish Peshmerga fighter looks over as he stands on the top of a humvee in front of an Islamic State militants' position outside the town of Naweran near Mosul. REUTERS/Zohra Bensemra

As 2017 draws to a close, the mood among leading pundits on the U.S.-led campaign to dislodge the Islamic State from Iraq and Syria might seem justifiably upbeat, even jubilant. After all, the accomplishments in the campaign’s first three years are many: eliminating key ISIS leaders, clearing the group from its so-called “dual capitals” of Mosul and Raqqa, and reducing the territorial safe havens from which it can plot attacks. It’s with some justification that, on December 9, Iraqi Prime Minister Haider al-Abadi declared victory over ISIS in Iraq.

But it would be naïve to toast to victory as the new year dawns. That’s not just because the last mile of defeating a terrorist group can be the hardest one, as the United States learned all too well from the lingering remnants of ISIS’s predecessor, al-Qaeda in Iraq. It’s also because regional challenges that Washington has suppressed by cultivating strategic ambiguity—deliberate vagueness in policy formulation that allows for different audiences to understand the same policy differently, thus allowing flexibility down the road—will become impossible to ignore and difficult to manage.

There are four chief strategic ambiguities Washington has perpetuated, partly because they’ve proven useful—perhaps even essential—to the campaign against ISIS. While some predated the campaign and others arose from it, they’ve already proven victims of its success. As these ambiguities prove unsustainable, the United States may be forced to do something very hard where Middle East policy is concerned: disappoint some who thought they could rely on Washington, and prepare for confrontation with others with whom it has tried to delay outright conflict.

To be clear: These persistent ambiguities weren’t mistakes on Washington’s part. To the contrary, my colleagues and I in the Obama administration who worked on counterterrorism and Middle East regional issues believed in maintaining these ambiguities at key junctures, even if we didn’t always think of them as “ambiguities” per se at the time. Especially as Washington held together a tenuous set of partners to dislodge ISIS without committing huge numbers of U.S. troops, these ambiguities helped propel the campaign.

Moreover, the inability to sustain these ambiguities shouldn’t be viewed as evidence of failure by the Trump administration, which has, to its credit, maintained momentum in the campaign against ISIS in Iraq and Syria. To some extent, these ambiguities were necessarily temporary. We should, however, worry that inept diplomacy and ideological fixation may be hastening their demise—a possibility with dangerous consequences.

One carefully crafted ambiguity we managed concerned the future of the Iraqi Kurds. Washington has been clear that its relationship with the Kurds—essential partners in the campaign against ISIS—is a special one. At the same time, Washington has repeatedly affirmed its commitment to a single Iraqi state, understandably a prerequisite for smooth relations with Baghdad, another critical counter-ISIS partner. But what of the Kurds’ yearning for independence, which puts them at odds with Baghdad? For years, a deliberately ambiguous refusal to deal with that issue was Washington’s holding line: The United States simultaneously committed itself to the territorial integrity of a single Iraqi state and to a special friendship with the Kurds in the country’s north. As the past months have shown, however, the issue will permit ambiguity no longer, as Baghdad’s tanks continue to reoccupy Kurdish oil fields in the wake of a Kurdish vote for independence. By allowing those tanks to roll in, perhaps Washington is already signaling its lean toward Baghdad.

This points to a second ambiguity involving the Kurds, but on the other side of Iraq’s border with Syria. There, the Syrian Kurds have been indispensable in shrinking the safe haven ISIS once enjoyed, from which the group plotted terrorist attacks worldwide. But the Syrian Kurds, too, have ambitions for at least a certain degree of autonomy, if not outright independence, that cause palpitations in key regional capitals—namely Damascus, which seeks to reassert control over all of Syria, and Ankara, which views the Syrian Kurds as indistinguishable from Kurdish terrorists responsible for years of bloody attacks inside Turkey.

What of the Syrian Kurds and their desire for at least semi-autonomy within the Syrian state? Washington has remained ambiguous on this question, thus ensuring that the Syrian Kurds remain a vital partner in clearing ISIS from strongholds such as Raqqa while also maintaining Turkey as the host for counter-ISIS operations launched from Incirlik Air Base. But with Raqqa cleared and Damascus—with Moscow’s backing—already consolidating its control over war-torn Syria, Washington will soon be forced to show how far it will go to support the Syrian Kurds.

Also jostling for influence in post-ISIS Syria is Iran, another key partner of Damascus. Washington has, of course, never been ambiguous about its view of certain aspects of Tehran’s behavior, such as its support for terrorist groups like Hezbollah. But when it came to Iran’s role in the fight against ISIS in Syria, the United States has clung to a third ambiguity: accepting that the enemy of one’s enemy may be tolerable as one’s friend, in certain respects … for a time. That time is running out. As various military forces collide in ever-tighter, now-ISIS-free spaces in Syria, U.S. forces are shooting down Iranian drones in Syria’s airspace. How to deal with Iran now in Syria seems, as drones fall from the sky, a challenge past the point of ambiguity.

Finally, there’s the future of Syria, and Bashar al-Assad’s role in it—and the role of his patron Vladimir Putin. Given the statements emerging from Washington at various times avowing that “Assad must go,” describing Washington’s approach to this issue as ambiguous may seem odd. Of course, that call has never been fulfilled, despite Assad’s butchery. What, then, is Washington’s real “must-have” for Syria’s future? A new constitutional structure that, at least in name, makes Assad something other than Syria’s “president,” even if in practice he retains a dominant governing role? Semi-autonomy for the Kurds? Whatever it is, with ISIS playing less of a role in dictating how the United States thinks about Syria and Russian military forces increasingly provocative toward U.S. forces within Syria’s borders, the window for ambiguity is quickly closing.

These ambiguities may have been inherently unsustainable. But poor coordination in Washington, tone-deaf diplomacy abroad, and ideological approaches to foreign policy may both accelerate their demise in 2018 and make them needlessly dangerous. For example, Secretary of State Rex Tillerson’s ill-timed call for Iranian-backed militias to disband or leave Iraq clearly exacerbated the already serious dispute between Baghdad and the Iraqi Kurds. Likewise, the mishandling of key issues in U.S.-Turkish relations aggravates the question of the Syrian Kurds’ future and raises the odds of a crisis between Washington and Ankara.

The retreat from ambiguity would be a difficult path for any administration to navigate—there’s a reason the United States hasn’t taken sides in these fraught rivalries and conflicts. Amid all the chaos within the Trump administration, not to mention the State Department’s emaciated condition, even the fundamental focus needed to find a way through these challenges and lay the groundwork for a more stable region is lacking.

The end to America’s carefully cultivated strategic ambiguities in the Middle East may be inevitable. The skillful management of difficult diplomacy is, however, a matter of choice and skill. As we keep our eyes on the winding road ahead, we can only hope for able drivers.

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