[philwelch]

Cold blooded killers aren't synonymous with psychopaths. It turns out that many of the Nazis weren't psychopaths, but rather psychologically unremarkable people whose institutions and culture allowed them to collectively perform acts of evil over and above what any of them could have done individually. This is called the "banality of evil", and it became widely understood after the Milgram experiment and the Eichmann trial.

Groups of people have always been more ruthless than individuals. Psychopaths are remarkable not in their ruthlessness but in their ability to achieve it all by themselves.