I back the war, because whatever the reason a bunch of anti-west extremist with weapons, is never good. The reason The public got into the war was 9/11. The reason the military got into the war was because of Bush's botched search for nuclear warheads. In the end, the CIA found no evidence of Nukes, but Bush (or someone under him) changed the reports to make them sound more imposing.
I don't know about the oil idea. Wouldn't we waste more oil using all those big war machines, planes, tanks, etc? I don't really know, but I would think that would drain out own resources.