there is something inherent in our nature to form ourselves into groups, tribes, gangs. Once we do this, the "other groups" become the enemy, and competition begins. When a particular group wins and dominates the others, it starts a nation. that goes on until another nation dominates instead.
i agree. it really does seem very hard for us to get past this basic wiring in our heads.
Pete2
All animals that form societies have outcasts. Also, I think it's inherent in animals that form large, very organized, and cooperative societies to go to war. IIRC, ants also have been know to wage war. Technology just allows us to do it on a larger scale.