It looks like the US under Obama is actually making a smart move on the Middle East. Recent advances against Islamic State by the ‘Syrian Democratic Forces’ are heavily backed by US firepower.
The SDF is essentially a Kurdish front group, and Turkey has been warning anyone who’ll listen against helping Syrian Kurds. This has prevented the US and others from meaningfully backing the Kurds, despite their consistently proving they can tick Western boxes by being capable fighters and not extremists – about the only group in Syria to fill both those categories.
But the Turks are a toothless tiger, and, with their earlier help to Islamic State, have arguably done more to worsen the situation in Syria than any other country (with the notable exception of Iran). (Though I note they have absorbed hundreds of thousands of refugees.) Their bluff should have been have been called years ago. It appears it has been now.
Here’s a good article from the Washington Post.