When hitler's war campaign started failing he had to choose between funding the war effort and funding the death camps. He chose the death camps and they kept them running full bore knowing it would cost the nazis the war and him his life.
If his goal was to cause as much death and human suffering in the least amount of time, he succeeded at what he wanted to do. So hopefully this next one ends a lot faster. I don't think trump could 1 up hitler unless he set off nukes. hitler went through much more trauma and it transformed him into an archetype of evil.
Psychiatrists that looked after hitler in WWI claimed a demon came to him while in days of hallucination and showed him how to kill people in mass, telling him about gas chambers. The hallucinations where from being trapped under the rubble of a building in WWI while a nerve agent, I think mustard gas, tortured him and drove him to insanity.
He was rescued from the building and brought to the psyche ward where he screamed and hallucinated for days. I forgot the book but they where speculating that the doctors kept him hallucinating because they were fascinated with his interaction with the demon, or they where just really sadistic, I can't remember.