Gulf War had nothing to do with Religion, if it was why would Saudi Arabia the holiest land of Islam support the US to fight Iraq, another Islamic country? Iraq wanted to invade Kuwait (another Islamic country) for Oil and land, and the US who was once allied with Iraq decided to invade Iraq to defend Kuwait.
I highly doubt that 'god' told Bush to invade so he did (he said it to please the evanglist lobbies especially), we all know how it went (WMD's etc) don't blame Religion for the war in Iraq, in fact we now have facts that Iraq had nothing to do with 911! Leaders always try to please the clerics/priests, its part of being politics!
Religion was not used to start World Wars, Are we also forgetting about Nationalism? Thats a big one right there. How about the Cold War, Capitalism/Communism? I don't mean to be offensive to anyone but how about Darwinism (think about guys like Hitler, superior race ideologies, survival of the fittest etc)?
The source of all evil (even if you don't believe in religion)? I'm sure Greed and (the want/need of) Power have alot to do with it etc. We live in a world with Corporations who we all know are greedy regardless. Its not necessarily the people who run it, its what a Corporation is...an imaginary individual with rights and freedoms that is taxed like an individual...
Look at Africa? The perfect example to look at how the world is...was it Religion that made the continent as it is now? Sure you can look at whats happening in Darfur, two Muslim tribes fighting each other, over a million dead does it have anything to do with Religion? Absolutely not in fact the cause of the war is tribal! One tribe has a nose shape that the other doesnt (look into it, its ridiculous! It sounds funny, But people are dying!) etc.
So please when people start saying Religion is the source of evil and start using guys like UBL as part of an excuse really need to wake up and learn something for once, even if you have no faith at all, there are MORE important issues to look at it. We are too comfortable these days... I can admit that....