The Kurdish flags now fluttering over Kobani after four months of fighting demonstrate that the Islamic State can be beaten on the battlefield in Syria. Plentiful U.S. air power ― some 750 airstrikes ― combined with determined allies on the ground can get the job done.

That’s less encouraging than it might be, though, and not just because success in Kobani will be hard to replicate elsewhere. To truly end the fighting in Syria and defeat the IS, the U.S. and its allies will have to undertake the distasteful but necessary task of negotiating with Syrian president and war criminal Bashar al-Assad.

Kobani is unique in Syria in two ways: The Kurds who live there, though they are Sunni, don’t identify with the IS or its caliphate-building project. And Assad and his troops aren’t fighting in the area. In contrast, outside Kobani, in Sunni Arab areas of Syria, every bomb that the U.S. drops on the IS ― and not on Assad’s Alawite-dominated regime ― makes it harder to find Sunni allies to fight the IS in the way that the Kurds did, because the rebels think the U.S. is helping Assad.

As a result, in recent months, the IS has been able to expand its territory and absorb other opposition militias. This has led some in Washington to suggest that the U.S. expand its coalition in Syria to attack Assad’s forces, too. Yet if Assad were to be toppled, the vacuum would just be filled by the IS, and Assad’s fellow Alawites and other minorities would be slaughtered. U.S. officials have rightly avoided that nightmare.

Instead, the U.S. conflicted Syria policy has become stuck. The current plan to begin vetting, training and arming the moderate Syrian opposition this spring is unlikely to unstick it. The only way out of this appalling stalemate is to come to terms with Assad ― without letting him back in control of Sunni Syria.

What is happening in Syria and, more broadly, the Middle East has been called “the Great Sorting Out,” in which the region is re-dividing into homogenous Sunni and Shia territories, with minorities squeezed out or eradicated. It happened across Europe at the end of World War II, and it almost happened in Yugoslavia after the collapse of Communism. This can be a long and bloody process.

If the Middle East is to avoid conflict of that scale, and the IS is to be denied its caliphate, Syria will need some form of soft partition, similar to what the 1995 Dayton accords produced in Bosnia. This would remove Assad from the battlefield and so allow ordinary Sunnis to focus on wresting control from the IS. The end result, as in Bosnia, would be a weak federal state in which the main sects and ethnic groups control their own security.

A Syrian Dayton accord is unlikely at the moment ― for one thing, Assad has not yet suffered a major defeat of the kind that brought Bosnian Serbs to the negotiating table. But Assad’s backers in Tehran and Moscow have increasingly limited resources to support open-ended war.

Nevertheless, the U.S. and its allies should be ready to deal with him to end the bloodshed in Syria ― just as they once dealt with another monster responsible for mass slaughter, Serbian President Slobodan Milosevic. Then as now, negotiating with a dictator to end a war does not preclude bringing him to justice after it is over.

Eventually Assad will have to recognize, as he does not yet, that he will never again control all of Syria. He has killed, tortured, starved and displaced too many of its citizens for that to be possible. The sooner he makes this realization, the better the coalition will be able to focus on an even graver threat: the IS.
 
(Bloomberg)