My father pulled the pin and retired from the local government indoctrination/daycare facility in the 1990's, but he had been noticing the declining state of history textbooks since the mid-1970's. There is always the long march with the left.
Always.
At some point in the '80's dad had to pick up some college hours, which led to being subjected to Gwynne Dyer's War as the cornerstone of an entire course. I'll just say that pater was decidedly not happy with much of it, but a credit was a credit and what was presented could be ignored. This corresponded to his noticing how the rot was accelerating in that timeframe between when most male educators were WWII or Korea vets and when they would all be retired.
Mr. niteowl77
Q