The Milgrim study was not quite as bad as it seemed or was reported. A substantial proportion of the "torturers" had figured out that it was not real. Several more protested that it was wrong. Those who did continue were convinced by the researchers that what they were doing was for the greater good.
However it did show that the separation of the executioner or torturer from the victim seemed to enable more viciousness.
Collateral Murder video leak from Wikileaks may better exhibit this effect.
