You know, I'm as militant an atheist as you're likely to come across in this country. Get me going and I'll bore you to tears with strident lectures on the ludicrousness of a worldview based entirely upon bizarre and illogical fantasies dreamt up by mystics in an age without soap.
That said, I'd no more tell a man that his religion is a ridiculous, childish fiction without provocation than I'd tell him his wife is a hideous old boot and his children as thick as shitty jam, even if the latter were true.
I realise that, in the pursuit of human enlightenment and progress, I should really be going Defcon One and nuking every religious believer I meet, but I have this whole basic human decency problem with going radge at strangers and friends alike for their nuttier notions.
Anyone who believes that the world operates according to the will of a benevolent intergalactic space hero is in for a brutal and horrible WTF? moment sooner rather than later, and I'm more than happy to piss on their chips if they're getting all up in my grill about it. Truth is though, most people don't.