What is the contribution of atheist for building the world in peace?

A lot of atheists are Humanists. Humanism is a philosophy of peace.

hey dude, it all started with religion thing. from time immemorial people are fighting for their religious belief to be superior. whereas an atheist thinks about humans emotions and the society. religion was brought to get the people into line, like disciplinary act. that aim has gone to ditch, then why all those things. people, vietnam is a country which has experienced the worst war crisis, destruction, starvation and still it's one of the technologically advanced coutry because of the 85% of atheist living there who believe in themselves for thier country's upraisal. got that??

I do not know

How would an atheist not contribute. Just as they have no God, they have no Devil. Just because they have no God does not mean they are violent or war loving. They are different than you and you should just take it as that, different and not just assume that they would not contribute. I am not atheist but I support diversity in this big world of ours.

Atheist isn't equal to evil or violent or peace-hating! It may denote a stronger belief in science or a rejection of faith, but not necessarily a rejection of morals!