Ontrus

How often does it happen that the police gets infiltrated itself?

You did not ask me, but I'll tell you as a German: Absolutely not.

The partition was viewed as a tragedy by people on both sides. What especially worried many was that in case of a war you'd be ordered to fight your brothers on the other side. Also, East Germany prohibited visiting relatives and exchanging information. You probably heard of the Berlin Wall built to keep citizens from escaping. Formally West Germany never even acknowledged that East Germany was another country while being accepting every of their citizens that managed to flee. Every political party apart from the Greens supported reunification. There was no controversy about that.

Immigration wasn't a big issue at all back then except for the vague idea of kicking out the Jews. Hitler mostly got elected because of an economic crisis and the Versailles treaty, both of which were unsolved by the Weimar republic that could hardly prevent civil war.

When Hitler came to power, it was absolutely clear there'd be a dictatorship and the abolition of democracy. His party was unabashed about it and there had been a coup attempt about a decade earlier already. Yet a lot of people did not mind and thought it might actually be better since democracy had failed so badly.

People stating why they voted for Hitler in German, recorded in 1983 (a different time, obviously).

For German-speakers, an article from 1960 when this "Kameradenerziehung" still existed.

A hundred years ago, even countries like Britain were effectively still run by a few aristocratic families. And some places might enormeously benefit from industry/technology even if they are no democracies -- indeed, I'll claim that there are populations who'd be so horrible at self-government that a benign aristocracy/dictatorship might work out better for them.