EGOmaniacs or Survivors?

I was watching The Believer with actor Ryan Gosling as the main character, an anti-semite who is a young jewish man himself.

I really enjoyed seeing the point of view of someone who is born and raised to believe one philosophy to one day feeling the need to completely destroy that very philosophy. Sure it's just a movie that I watched but how many people out there have really felt this way? I know many atheists that were once Christians. Sure they may despise Christianity and anything or anyone Christian affiliated but how many of them have grown to hate it so much that they would actually try to harm these people?


I also came across a quite terrible but amusing movie An American Carol who pokes fun at anti-American documentors, Muslim terrorists, along with many others, but what I found most amusing was them poking fun at Radical Christians here's the video:

Sure it's funny or highly offensive but in all seriousness what gives any people the right to enforce their beliefs/philosophies/ideals on others? What is it that triggers something to go of in someones head that it is the right thing to blow someones head off just because they don't believe, think, or feel the same way as them?

As Americans today we may automatically assume I'm referencing muslim terrorists. But what about the Crusades? The Holocaust? The Civil War?


So far I understand why religion came to be but where/how does death and destruction play into all this?

Is it all about ego? Or is it really a matter of survival?