Ugh. Historical revisionism and propaganda blows, no matter who does it.
Learning material should always be politically neutral no matter what - though it's kinda pointless to expect something like that in most cases.
Warning: The preceding message may or may not have included sarcasm, cynicism, irony, full stops, commas, slashes, words, letters, sentences, lines, quotes, flaeed gramar, cryptic metaphors or other means of annoying communication. Viewer discretion is/was strongly advised.