I think you both forgot about a slightly bigger & more recent one, that little Unpleasantness Between The States.Christ, some of you are pathetic.Since the actual establishment of this country, we have never had a foreign conflict take place on our own land. I think that this has influenced how American's see conflict and war in other countries. Since they have never witnessed the destruction and the long time evidence of war, they don't think it's a big thing. There is a detachment to seeing bodies of civilians in pictures and that is how a lot of people like it.
However, I agree with the idea that it's been a long time and most USAnians are not particularly sympathetic to having a war in your country.