I see that it's time for an Abu Bakr al-Baghdadi blingee.
Even if we somehow drive ISIS out of Northern Iraq (which is going to take more than a few airstrikes and cost the lives of more than "some" civilians), they'll be back. A direct fight against the the United States, the symbol of the sinful West, will be a huge motivator for these fanatics and a boon for recruitment throughout the Middle East. Then, we'll either have to stay and perpetually pour even more blood and treasure into this Godforsaken desert, or leave and see them return even stronger and crazier than before, like angry hornets (if that happens, the interventionist crowd will say we have to stay because "we created this mess").
This is foreordained, is it?
The I. S. took advantage of western Iraq's grievances against its government in order to establish itself in that region. The surest way to decapitate the Islamic State is to address those grievances (lack of say in the government) (which is in the process of happening, as I understand it), and/or convince the local Ba'athists and Sunni tribes to revolt against their "liberators". The latter might happen naturally, if the I. S. continues to blow up sites that are holy to Sunnis.
The Peshmerga was more than a match for the Islamic State until very recently. Now that the I. S. is armed with the mortars and artillery that it recovered from the fleeing Iraqi Army, the Peshmerga is outgunned. Since you oppose leveling the playing field with US airstrikes against I. S. mortar and artillery positions, do you support leveling the playing field by arming the Kurds with that kind of heavy equipment?