I think you have underestimated how much culture determine people's attitudes.
Consider a normal guy from my home country a few hundreds of years ago. He believed that he will only go to Heaven if he dies well in battle and is hence really scared of dying from disease. He wasn't a psychopath; he loved people and would die for his friends etc. He is normal for a clan society.
The same genes sit in me, which sincerely hopes never to have to maim or kill anyone in my life. Those human genes program us to be very programmable with the present culture. A powerful tool can often be misused.
The trick is to make the culture stay "nice". And to not have neighbours from clan cultures.
I would wager both probably heavily involve genetic material having a leg up on others thanks to hundreds of thousands of years of genocide and rape.
None of this will factor into a reasonable definition of "sane".