He had the technology to do more harm, more quickly. Morally or ethically speaking, the three you mention (plus Stalin, Mao, Pol Pot and a host of others) were probably much the same.

If we had wanted to, we could have hanged Napoleon after the war for war crimes - executing prisoners of war and other murders. There were no parallel rules of war in Genghis Khan's culture, but he committed crimes against humanity every time the opportunity came up. And so on.

The only difference is that Hitler had railways, a chemical industry, a documented population and modern techniques of surveillance and policing to help him. This all helped him to boost his score, but the others would have been as destructive if they'd had the means at hand.

^^^

PS: Napoleon lost as well. Big time.

First off, Napoleon isn't exactly cherished in france today. They did exile him to a tiny island so that he wouldn't bother them any more… And Ghengis Khan is from Mongolia — what the hell else do they have in mongolia to be proud of. Let them have good ol' Genghis.

Hitler is hated more than these guys because while did lose (historians now debate whether or not Napoleon won his wars becuase it took him just shy of a million men to do what he did. He lost far more than he killed…) he didn't really play to the traditional rules of war. Kill who you need to take over the territory/populace and allow the others to live so that they can be your tribute payers. Hitler tried to kill entire populations of people. He was sick. Despite what people say, there are rules of war.

I think we must make clear diference between Hitler and Genghis Khan on one side and Napolean on the other side.
Napolean was a great deliverer. it is the British who have made him look a tyrant. He implemented the idea of Liberty, equlity and fraternity. Where ever he went he was truly delivering those people from old feudal system, and sawing the seeds of modern days democracies. In fact his vision of united Europe was far more ahead of his time. He was thinking of united Europe and internationalism when as yet democracies had not yet developed.
Whereas Hitler and Genghis Khan were ambitious despots . if Hitler had succeeded, humanity would have slipped back in its advance and evolutionary processes would probably have slided back at least a 1000years.
Genghis khan was a brutal, blood thirsty, and cruel King.
Napolean represented force of light and truth, whereas the other two forces of destuction, and evil satanic instruments of darkness.

Modern technology and people involved with what Hitler did are still living and telling the story. We have photographs and film, physical evidence, of what Hitler did.