How bizarre that the biggest obstacle to finishing the war against the Islamic State and beginning the stabilization of Syria is America’s supposed friend and NATO ally Turkey.

Secretary of State Rex Tillerson made the latest attempt to mollify an angry Turkish President Recep Tayyip Erdogan in a three-hour meeting in Ankara Thursday. But this may be mission impossible: Granting Turkey’s demands would make Syria more unstable and prolong the threat of radical Islamist terrorism there.

The U.S. goal is “getting to yes” with Erdogan, says a senior administration official. To that end, the United States has crafted a tentative package meant to appease the Turks by offering them a buffer zone in the Kurdish enclave of Afrin, joint Turkish-American patrols of the Manbij region where Erdogan has threatened an “Ottoman slap” if U.S. troops don’t leave and gradual dilution of U.S. ties with a Kurdish-led militia that Erdogan despises.

To coax agreement, U.S. emissaries have prepared what amounts to a Venn diagram, showing how closely American and Turkish interests overlap in the region — except for on the Kurdish issue. That’s like saying a couple have an interest in staying married, except for the fact that one accuses the other of an affair. Certainly, American and Turkish interests should converge; but if so, why does Turkey imprison American citizens, accuse Washington of fomenting a coup and violate U.S. sanctions against Iran?

Nobody wants a violent rupture with Turkey. But seven years into the catastrophic Syrian war, observers need to admit some ground truths: The Turks allowed thousands of foreign radical Islamists to flow into Syria and create bases from which they threatened Europe and the United States; these terrorists would still be in their capital of Raqqa, planning attacks, if the United States hadn’t partnered with the Kurdish-led Syrian Democratic Forces militia that Turkey hates so much.

Meeting Turkish demands would mean abandoning the SDF, which did the fighting and dying against the Islamic State. Even if the United States were ready to commit that amoral act in the name of realpolitik, the result would be more chaos in Syria, not less. The Turks simply don’t have enough disciplined, reliable military power to stabilize the areas the SDF now controls. The United States would create a free-for-all that would make Lebanon look tidy by comparison.

Here’s a catalogue of the craziness in the Syrian battlespace over the past month: A former al-Qaeda affiliate has shot down a Russian jet, using a Chinese-made missile; Kurdish forces have shot down a Turkish helicopter, using an Iranian-made missile; Iran has flown a drone into Israel, across Russian- ­monitored Syrian airspace; Israel has bombed 12 sites across Syria in retaliation; and the U.S. response to a Russian-backed sneak attack on oil-and-gas fields near Deir al-Zour killed perhaps scores of Russian mercenaries, overflowing the local morgue.

Syria is now riven by “converging forces with diverging interests,” warns a senior Pentagon official. Staffan de Mistura, the U.N. special envoy, said Wednesday that it is as “violent, worrying and dangerous” a moment as any since he took the job four years ago.

What’s the answer to this toxic mix? Not empowering Turkey’s deeper meddling, surely. The path out is a steady, patient advance of the faltering Geneva negotiations to extend the power and authority of a reformed Syrian state and military. For the United States, that means biting the bullet and working with Russia and the Syrian regime — two untrustworthy but essential partners.

Russia actually took a step forward this month by drafting a new Syrian constitution that would grant limited autonomy for Kurdish regions in a newly decentralized Syrian state. The Russian draft would reconcile Kurdish and Arab demands, and some U.S. officials see it as a basis for serious talks. But other administration officials view Russia as a wrecker that uses “bait and switch” tactics to advance its interests and Iran’s, at the expense of the United States and its allies. What President Trump favors is anybody’s guess.

The core problem in this latest phase of the Syria mess is similar to what got us here: The United States has the strongest military force but doesn’t know what it wants, politically. Turkey fulminates and demands American support but lacks the power to stabilize areas it seeks to control. Russia has the steering wheel, diplomatically, but has no trust from its passengers and no gas in the proverbial fuel tank.

Here’s a thought experiment: Should the Kurdish-led SDF be disbanded, as Turkey wants? No! That would create a power void and more instability. Instead, the SDF should become part of a new Syrian national army — working with Damascus, Washington, Moscow and, yes, even Ankara.

Twitter: @IgnatiusPost

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