Seriously, its not the religion itself that creates fanatics. Even peaceful religions like Daoism and Buddhism have had its fair share fanatics.
The world can be thought of as being split into two groups - those who want to get along and those who don't. We need to make the first group bigger and the second smaller.
Oops. I generalized!!! GOSH NOW I'M A FANATIC I SHOULD START A NEW RELIGION CALLED DUALISM AND PROMOTE THIS FANATICLY!!
Oh wait, dualism is taken.
Oh well. Where was I? Oh yes, YOU MUST OBEY THE GOSPEL OF THE FLYING SPAGETTI MONSTER OR YOU WILL BE DESTROYED. RAmen!