Freedom dude,

You're really confused. Atheism means lack of theistic belief as opposed to Stalin, polpot and Mao who may have been atheistic, due to their suppression of religion, but were driven by an idealogy --communism to be exact. To say they killed because they were atheists is "moronic" at best. And you don't see atheists go around bombing and killing each other for not adhering to their god, cause there aint one!