Britain has joined a war against Islamic State (Isis) within a political framework that guarantees frustration if not failure. The House of Commons was rightly wary of another open-ended foreign intervention in Iraq, Syria or anywhere else. But, while MPs are conscious that Britain is entering a minefield, they were much less good at identifying where the mines are and what, if anything, can be done about them. As in 2003, the US and Britain are plugging themselves into a series of inter-related conflicts in Iraq and Syria in which the main players have very different agendas from what they pretend.
Take the current Isis offensive against the Kurdish enclave of Kobane in northern Syria on the border with Turkey, where 300,000 Kurds are squeezed into a smaller and smaller enclave as they battle better armed Isis fighters. Some 200,000 Syrian Kurds have already fled across the Turkish border. Here, if anywhere, the US could have deployed its airpower to attack the advancing militants. It was US air strikes that helped to save the Iraqi Kurdish capital Erbil in August so why not do the same for Kobane?