Any idealism taken to extremes...
Any idealism taken to extremes be it faith, politics or race will always end in bloodshed. Religion has both good and bad points, many of the most inspiring structures in the world owe there existence to religion, the sound of choirs raising there voice to sing give great joy to those who listen. Religion offers solace and support to many in need in need, most of the philosophy on how we should live our lives held within the texts hold true today. The sight of people praying is very calming even if as I do you not believe in any organized faith.
However to believe that religion is the only way one can live a good life is misguided. And the only difference between someone who follows any of the Abrahamic based faiths and a true atheist is one god for those who believe reject all others from Belobog to Zeus and therefore teach us to be intolerant of anyone who does not believe or disbelieve the same as us.
Until we can learn to accept that although we are different in many ways, we are all fundamentally the same. And that shoving your views be they athiest or religous down others throats in the false belief that you are right, as who truly knows? Only causes greater misunderstanding and resentment then we have no hope of tolerance or peace within the world.