Why do theists make the claim that the worst mass murderers in history were atheist?

[Kirk]

I know this is beating a dead horse.We all know Hitler,Mussolini were catholic and you'd be hard pressed to find an organization with more blood on it's hands...but what about Pol Pot and Stalin?
Do they forget that Russia is now and has always been predominately Russian orthodox and it was people of this faith who carried out Stalin's orders?
What about Pol Pot? Did the entire country simply decide to stop being Buddhist?

 

[shadowsajjad]

Satanists are the main murderers

 

[EscapeBlade]

Yeah seriously.

Plus, if you add the old testament on, the scales break.

 

[Meowzers]

mao and stalin were mass murderers and were atheists

 

[Al K]

I'd say it's a wash