Fareed Zakaria offers a useful reminder why U.S. policy in Syria is so muddled:

But if you consider the major groups vying for control of Damascus, the United States is against almost all of them.

The fact that the U.S. can’t support any of them should make it clear that the U.S. has no business being involved in the conflict at all. The hunt for the elusive “moderate” opposition has been driven by the weird desire to find some faction in the civil war that the U.S. can support without openly endorsing jihadists. While interventionists imagined that the U.S. automatically had “allies” in Syria that it needed to aid, the reality was that there was never any side in the war that the U.S. could justifiably support that had any chance of prevailing over the other forces. Instead of taking the lack of obvious allies as a warning to stay out entirely, the U.S. keeps trying to find a way to take sides.

The desire to take sides stemmed at first from hostility to Iran: if Iran backed Assad, the U.S. had to find enemies of Assad to support. It didn’t matter that the U.S. would gain nothing from regime change in Syria, or that pursuing it might impose more costs than it was worth. Hawks just wanted to inflict a loss on Iran. Now fighting ISIS has taken priority, but not so much that it overrules the old hostility to Iran, which is why so many hawks now propose fighting both Assad and ISIS at the same time. The U.S. has scarcely any more effective allies on the ground now than before, but instead of rethinking the entire project the U.S. keeps stumbling ahead with a war in Syria that it doesn’t need to be fighting. All of this comes ultimately from our political leaders’ inability to recognize that there are many conflicts that the U.S. should avoid all together.