Turkey has swung into action with air strikes - not against the jihadists of the IS group who are besieging the Syrian border town of Kobani, but rather against the outlawed Kurdish Workers Party. It's the first attack against PKK positions in Turkey since a ceasefire went into effect two years ago. This comes as Washington is trying to persuade Turkey to allow the anti-IS coalition to use its Injirlik air base. Is this shaping up to be a coalition of the unwilling?