There’s an excellent article “Why Religion Must End” at this site. The author proposes that religion is the cause of a great deal of hate and strife, which seems to me to be true. The middle east has been at war for thousands of years. Right now they are killing us while yelling “God is Great” Just recently some cartoons depicting Mohammed resulted in violence and the torching of an embassy, although ironically only when we post them. The same cartoons were posted in Muslim newspapers without a peep. My neighbor moved from Egypt because of religious persecution (Muslims again). Just so I’m not picking on Muslims, the Crusades was a war driven by Christianity.
As the article points out, some of what religion proposes is good – such as the parts that propose generosity. When I was poor in Alaska my neighbor was a Mormom and he let me stay with his family for a couple of months until I found an apartment. However, rational thinking has the same effect and comes without the bad parts such as intolerance.