re: why do all African Americans defend each other?

You want the simple answer, which has been played out time and time again.

We will never be cohesive, as a people, a race, religion, ideology or whatever.

It's always been this way, and will continue to. Where has that gotten us? Still same old shite, more technology.

Edit: There is an end game, and the way it is, is the way it was supposed to go. We aren't changing that.