It’s not that President Barack Obama didn’t have a coherent vision of what he wanted to achieve in the Middle East when he came to office. The guiding principle of his policy was and remains very simple: an end to occupation—the American occupation of Iraq and Afghanistan, and, yes, Israel’s occupation of the West Bank.

If he didn’t articulate an overreaching Obama Doctrine, spelling out unequivocal principles, that’s because he’s a realist, more or less in the classic vein of Hans J. Morgenthau, whose textbook you may remember from Political Science 101. Realistic policy is deeply suspicious of any doctrine; inevitably it smacks of what Morgenthau called “the crusading spirit” (think of the Global War on Terror) and it is “never true, because it is absolute, and the affairs of men are all conditioned and relative.”

Looked at from that perspective, Obama’s policy is quite coherent, and after years spent trying to extricate Americans from the disastrous occupations begun by the Bush administration, it was perfectly understandable. The public in the United States won’t support more military adventures with boots on the ground in the Middle East.