There's a big problem with President Obama's new war against the Islamic State in Iraq and Syria (ISIS): it can't be defeated by military means alone. And the more Obama escalates, the more he runs the risk of forgetting that once-central element of his policy— with disastrous consequences.
Obama's new strategy in Iraq and Syria, announced in a Wednesday evening address, rests on the theory that the Iraqi army, Syrian rebels, and the US Air Force can defeat ISIS on the battlefield. That might be true — if all of the political stars align properly. But by declaring an open-ended, years-long war against ISIS, Obama risks trying to solve a fundamentally political problem by military means.