Us against them. Us is always right and them is always wrong. Simple, right?

That does seem to be the basis of much of human behavior (or, at least, the rationalization for it).

I see this most dramatically in the foreign policy of nation-states, where naked selfish ambition is often justified on the basis of We Are Good and Noble, whille others engaging in similar behavior are decried as They Are Evil and Dangerous.

Yes.

It's kinda frustrating but I guess it is the way of the world and will always be the way of the world. I think many folks never ever even question it. It seems to be a GIVEN. Mahalo for your answer OS! :)

i dont think things are ever that simple