@Walter Hinteler,
I was thinking about the Nazi example before you posted it because it is interesting. Actually, I think the slaveholder culture in American history may be a parallel, although there are important differences.
It is impossible for a historian to understand Germany in the 1930s or America in the 1830s without being able to view cultural norms from the perspective of Nazis or slave owners. A historian needs to be able to understand motivations and events detached from modern understanding.
Of course, viewing things from the perspective of an everyday German Nazi supporter in 1930 is not appropriate for a elementary school student. It is part of having a complete understanding of history
I read an elementary school teacher was fired for javing students consider the world from the perspective of a slave owning family. I see why she was fired... but on the other hand, that is part of the study of history.
These are not easy issues.