I recommend reading War is a Force that Gives Us Meaning by Chris Hedges, it's bout the corrupting aspects of war. It goes on saying that religion often isn't the source of conflict but is used as fuel, among other things.
This is ignorant in my meaning, there has always been borders between people and perhaps always will, it's a common and powerful tool when creating unity within a group to direct and focus it's negative feelings towards another group. And painting the US out to be superior to all others makes me think you should take a vacation sometime, out side the US.
I wasnt referring to any kind of superiority simply that everyone who resides in the whole world ethnically and religiously also reside together in one place so that there is a common thread so why isnt there world peace?