Buzzfeed News quotes Rafik Hariri Center Nonresident Fellow Aaron Stein on the United States involvement with the PKK to fight ISIS:
The emergence of Rojava has also complicated U.S. strategic calculations, angering Turks worried that it will be used as a base for operations on its territory. “Projecting forward, this is a major political headache that won’t go away,” said Aaron Stein, a scholar at the Atlantic Council’s Middle East center. The Pentagon’s aim of elevating the YPG as a tool to defeat ISIS conflicts with U.S. needs to keep Turkey, a NATO ally and a launchpad for airstrikes against ISIS, content. “It’s a heavy lift, and a political problem that will not go away in the near term,” he said.