Some like to believe that if someone doesn't subscribe to their brand of Christianity they are not 'true Christians.'

Hitler was a cherry picker, mashing pagan beliefs with a selection of ideas from the bible...but that doesn't make him an atheist.

The implication appears to be that someone of faith would not do terrible things. Which ignores the work of the church during the inquisition, scum like Ivan the terrible, etc....theists who tortured and killed.