Many atheists have a vendetta against Christians. Maybe something happened in their past.
Example: an ex-wife is raising his children as Christians. The anger and emotion is not with Christians but with the ex-wife.
I understand that, but how can someone logically claim to be an atheist and yet believe in God?
My guess is that the vendetta they have against Christians has much to with behavior that they persist in doing. This behavior, Christianity tells them, is totally contrary to Christian beliefs. Fornication, adultery, drugs, over-drinking, divorcing-remarrying (Catholic), pornography and such. People don't like that, especially if they have excuses for their un-Christian behavior. People buy into their own excuses so much that Christian absolutes are just TOO MUCH for them and thus begins the vendetta.
I'll show you, God, I won't believe in You anymore. That'll show You!