Religion has its good points as well, but it seems to do more harm in the end than good...at least that is what History has shown.Religion succeeds at promoting Unity....among like minded people, while having equal success in promoting disunity between the conformed and the others who think differently.
At least religion has provided good exercise for the right side of the brain. Try to imagine humanity and the course of human history if there had never been something that resembled religious expression. I don't think life would be so great if we were some uber-rational beings like vulcans from star trek... drunk
People unite around all sorts of things, including religion. When any group begins to share a common identity and values, it can create very dangerous and polarized conflicts. For example, chauvinism can be just as big a problem. That being said, the level of irrationality present in some religious conflicts can be astounding.