Calling "Civil War" Doesn't Mean It's Over

Jonah Goldberg asks if the war in Iraq is a civil war, why is this a civil war we should not take sides in?

OK, but here’s what I don’t get: Why? Why is it obvious that intervening in a civil war is not only wrong, but so self-evidently wrong that merely calling the Iraqi conflict a civil war closes off discussion?

Surely it can’t be a moral argument. Every liberal foreign policy do-gooder in Christendom wants America to interject itself in the Sudanese civil war unfolding so horrifically in Darfur. The high-water mark in post-Vietnam liberal foreign policy was Bill Clinton’s intervention in the Yugoslavian civil war. If we can violate the prime directive of no civil wars for Darfur and Kosovo, why not for Kirkuk and Basra?