Is it wrong to judge how people behaved in the past based on today's morals?

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If by "masses" you mean the absolute majority of the population, then yes.

As a German how do you view Nazi Germany? Surely it was a golden period of German history considering how much support it had?

For 12 years. That's a very short timespam for a German state. And it has very little support today, so your information is outdated.

I hear Kim Jong Un is a great leader as well, don't you know how popular he is in North Korea?

I don't. And if your knowledge about North Korea has the same quality as your knowledge about Germany, then you don't know either.