Politicians use religion to divide and conquer people. The main destructive impulse is generally the political objectives involved, and the religious divisions in a community become inflamed because of big political-financial games.

To blame it ON religion is facile. Religion is not the origin of the problem. Politics and economics are the origin of the problem. When you have people scheming as to how they can take over markets, land, and resources, that's when you have a fight...and if religion can be used as an excuse for that fight, it is used, but the fight does not generally stem from the religion itself. It just makes a darned good excuse, once the fight gets going.