We don't kill each other over them. (except maybe in Ireland, but they are mentally retarded anyways) In fact we go to each others churches for weddings and funerals, baptisms etc. in the real western world.
in Northern Ireland, again the issue is primarily historical and ethnic rather than religious. The Catholics wanted to keep the idea of being “Irish”, the protestants were originally Scots shipped over as they were ok with being “British” and loyal to the crown.