Der Untergang is excellent, but it's not (IMO) a depiction of a monster. It's a depiction of a tragically flawed little man with some very strong oratorical skills who unfortunately rose to very high political power in an unstable time and whose rise resulted in the development of a monstrous political system. It is the systems which are monstrous, and that sure wasn't the only one. There are several more mostrous systems around right now, usually run by tragically flawed little men who rose to very high political power.

They all imagine they are doing what is "right", what is just, what is good, noble, and proper. They think THEY are right. They're absolutely sure of it. (Just like most of the people reading these lines are sure they are right.) They're sure that those who disagree with them about anything are wrong. Dead wrong. Evil, in fact. And that's what makes them so dangerous. They'd rather be "right" than be merciful.

Hitler sincerely thought he was saving Germany from the most evil and terrible forces, and he created an evil and terrible system while trying to do it.

I see people very similar to Hitler in high places now. Some of them are governing in what we call "democracies". They are dangerous men, and they are in command of exceedingly dangerous powers.

But they are not monsters. They are just flawed men out of their depth. They're rather be right than be merciful. They're rather win the next battle than secure a lasting peace. They'd rather compete for final "victory" than share and share alike. The systems they have created are monstrous.