I agree. Our interest WAS the oil. In Iraq that is what we were protecting; that and fulfilling Israel's strategy for keeping its enemies weak (which backfired to some extent by strengthening Iranian/Shia influence). If our interest has anything to do with removing savage dictators for the common good, then the members of the commons must pay us. Only a foolish people would expend tremendous amounts of treasure and much blood just to play at being Captain America Goes Asiatic.
The trouble with removing dictators, is that more often than not, they hold together a country with several potentially warring factions, and the country immediately descends into an ungoverned hell.