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United States policy in Syria is at a crossroads. The current situation is untenable: the bloodshed continues unabated, while spillover threatens all the neighboring countries, and by extension, US interests. Powerful ethno-nationalist movements are stirring, most importantly among the Kurds, and are threatening to confront the international community with a new reality on the ground. Rival powers Russia and China (each in its own way), sensing American weakness following the embassy attacks and riots throughout the Muslim world in the last week, are positioning to cash in. 

On the other hand, there are simply no easy solutions in the country where a civil war is becoming more violent and intractable by the day. Such wars, as former CIA analyst Kenneth Pollack put...