The Lesser of Two Evils?

I was walking on my way to class when I noticed a poster in a window of this dorm room (that one weird dorm thats seriously right on campus). It was a simple white poster with black lettering that boldly declared:

OUT OF IRAQ
INTO DARFUR

Which honestly didnt make sense to me (I support some force going into Darfur of course, but I dont think that means leaving Iraq). I assume that this person opposed the Iraq War on the principle that all war is wrong--a classic anti-war position which is a title this person would most likely not object to--so what then, makes one war (Sudan) better/more moral/right than the other (Iraq)? Why is war in Sudan--which probably would cause a refugee crisis, would require a large number of boots on the ground and would involve setting up a puppet...er...interim government...so its like Iraq, but much bigger--more preferable than war in Iraq?*

I know, I know, there is a genocide going on in Darfur (but not if you ask Kofi and the UN, naw theres nothing going on there) but for all intents and purposes, it was going on in Iraq too. Someone might shout, "There's ethnic cleansing going in Sudan". Well, there was that too in Iraq--remember everyone's favorite, the Marsh Arabs? Both Saddam's former government and Sudan's current government are ruthless, brutal dictatorial regimes--one led by a man who liked to watch videos of women being raped and men being tortured while enjoying a morning cigar, the other is the top dogs in charge directing mobs of men on camel-back with wicked Russian rifles to murder Africans in an effort to take over the oil-rich south. In both cases it's Muslims killing Muslims even though the Q'uran says not to (though it does want you to kill infidels).

And well, there's the kicker. Sudan has oil, so if you orignally protested against going into Iraq on the basis of "No Blood for Oil", how do you work your way around that? If you objection to one war was because you did not want soldiers dying for a strategic resource, how do you justify supporting a war where said strategic resource is also located? Does the presence of oil change the equation?

What in other words, makes one war in a Muslim oil-rich country where a brutal regime is committing genocide against its own people different from war in another Muslim-oil rich country where a brutal regime is committing genocide against its own people? What makes one a war of imperialism and another a mission of humanitarianism? Strategic interest? Is war acceptable if a country has no true purpose for being there other than the kindness of its own bleeding heart?

What makes one war good, and another bad?

I know this is just a series of questions, but frankly I have no answers because I do not place myself in a moral quandry as such...that is, I do not claim to be either pro- or anti-war (though I would rather avoid the whole mess altogether). But I would love to ask that person who put that poster in the window these questions and hear what answers they come up with.

*This post is not about whether the Iraq War is right or wrong (particularly in comparison to Sudan), but rather how someone who is obstenibly anti-war decides what wars are right or wrong, which are campaigns of imperialism or humanitarianism.