I didn't know
When I learned about the holocaust as teenager in Germany, many people from the Nazi era were still alive and lived all around me. Being the curious person I always was, I asked them about what happened and their role in it.
"I didn't know" was the boilerplate answer. And as they were relatives and friends, I believed them at first.
Then in 1981 we got a new teacher for history and he exposed the lie. Or more precise: he got us exposing those lies.
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