I'm just watching a film set in 1023 when "the Arabs tolerated the Jews (and vice versa) but not the Christians". Even religious prejudices are not consistent. It's all down to the political and religious prejudices of the day. If we didn't have religion life would be much simpler, we could just concentrate on racism, or which football team you support. (Some) men (mainly) just want someone to fight, any excuse will suffice. Unfortunately the fighters tend to become leaders. Just another thought.