I don't believe that religion ultimately determines the quality of a person. A Christian can be intelligent, tolerant, open minded, everything that we as a society view as "good." I've met people like that, very, very smart people who were also religious. The fact that they believed in a god did not change their intelligence. The fact that I do not does not change mine.

Likewise, I've met some incredibly stupid atheists. Most of r/atheism, for instance, is banal and offensive. I use to be a great deal more militant about the issue of religion until I saw r/atheism, and I simply couldn't continue towards what I saw as the end result of that style of thought. I've also seen some incredibly stupid Christians, the people who fell for the goatse photoshop of clouds awhile back, or the people who honestly take the bible as word for word accurate.

These people would be just as smart or just as stupid with or without religion. Does religion play a part in shaping how bigotry forms? Yes, of course it does, but its not the source of it and its certainly not the key role, which in all honesty is probably severely repressed sexuality.

More often than not, religion is the excuse rather than the cause. Those who honestly believe the Crusades were fought over anything but money and conquest are not really well educated about the subject.