My father was one of the post-WWI military cartographers who redrew the map of North Africa using straight lines. As Dylan Ratigan said, those colonial boundaries created artificial territories and divisions that still contribute to wars and violence. So does the West's continuing perception of other cultures as lesser.
How many wars and interventions and political interferences have WE perpetrated just since WWII? According to William Blum 70, all of them carried out with little remorse. If we don't feel regret and horror for the chaos and huge loss of life we've caused we don't have a leg to stand on when we want others to stop their aggression. There's a big moat and beam story here (and I'm not religious).
We won't rethink warmongering unless we remove all our troops and military bases from around the world. I'm afraid though that such an obvious but radical step would need far more guts and creative thinking than the U.S. is capable of.