Why do we do evil things?

The emotional conditioning of a persons mind, to be able to commit such evil, by not seeing the moralistic side of it... in the name of race, superiority, fighting their own self perceived evils against them etc.... fighting for their own happiness.

When someone commits acts (good or bad) in the name of their (or their race, people etc) for the sake of happiness (either having great or just a little influence).... this will help their emotional conditioning to bypass all sense of morality.... in worst instances leading to hell on earth, for a person or a people.

A world beyond Hitler

Can we live in a world where acts against People can go beyond what Hitler can even imagine?

Yes... we are....

'Women are gang raped, often in front of their families and communities. In numerous cases, male relatives are forced at gun point to rape their own daughters, mothers or sisters,' she said.

After rape, many women were shot or stabbed in the genital area, and survivors told Ms Erturk that while held as slaves by the gangs they had been forced to eat excrement or the flesh of their murdered relatives.

http://www.rte.ie/news/2007/0730/rape.html