Without western air support IS would've won Kobane and the 4 million people living in North Syria would be living under a Takfiri boot right now, of all of the west's imperialism this one happens to have the best humanitarian result (by sheer chance, not by altruism).

While I get the sentiment, if you asked anyone in North Syria they'd tell you that they're better off for western intervention against IS (and the continued peacekeeper presence to stop Turkish invasion). It's not that clear-cut, although it still remains true that western military actions are done in self-interest and for imperialist purposes and 90% of the time they result in a worsening of the situation on the ground (Libya, Iraq, Afghanistan, Yemen, to name a few)