Every day is a gift, not a given right.
Most of us would fight for the wrong cause, because we want to live. That's one of the reason why tyranny works so well.
From what I understand, Hitler took advantage of Germany's poor economic status and its supposed "loss of glory" after losing World War I as a way to encourage people to join his cause, which involved blaming Jews and other groups for their bad economy (as Jews were stereotyped as greedy backstabbers and would go as far as crucify Jesus), as well as using pseudo-scientific racism that viewed Jews as a race whose members were locked in mortal combat with the Aryan race for world domination.
Obviously, the German public, including children in classrooms, being told that Hitler was a hero who was helping save Germany were being brainwashed with lies, but seeing as how the Hitler Youth had gained millions of children as its members, and was said to have been a big reason the Holocaust happened, the Nazi's lies had largely worked even though the public could have researched so as to find out for themselves what was true and what wasn't, but evidently, research, as well as humanity, didn't seem to be a priority for them.
There's definitely a responsibility to be had towards those that express malicious actions on the basis of lies, but there's definitely also a responsibility to be had towards those that spread lies in the first place, especially if it's children who are being told lies and are encouraged to believe them.
Its a thing that gets rolling and you cannot stop it, I guess. I fear it will happen again. In Germany the wrong political party is gaining more power again, even if we should know better. But history will repeat itself, people are dumb, people want to hear what they want to hear and don't think too much about it. People want to generalize. I don't know if it started with the refugee wave, or what, but it started some time ago.
Not everyone thinks the same, but many.
I wonder if it was the same with Hitler. I have to ask my father, born in 1935 a refugee from the Russian invasion and a survivor of terrible things I cannot write. I remember him saying that most people weren't educated enough, and Hitler gave them jobs and they were blind to see what was really going on. And some believed in him and what he said.