Sometimes moralizing is necessary. In Canada we had one teacher go into detail on the kidnapping of indigineous children and the residential schools they were sent to where they were often beaten or raped. I'm glad that teacher did that since many of my contemporaries were not aware of that history and some remain oblivious into adulthood. There's nothing worse for a nation than people having a false sense of pride in it (as we're seeing in the US currently).