Yeah, I agree completely. In fact, I think they're a substantial part of the cause. I guess the question is, why have we defined our groups in this way?

Do I really have something in common with a randomly selected black person just because they're black? Does a white person really have something in common with a randomly selected white person because they're white?

To me, the answer is so obviously "no", that the question is preposterous. If I have to pick a tribe at all, it's people who can see also this obvious truth.