In regards to the teaching of modern history in Australia for the final two years of high school, the first year has a high proportion of content related to communism and the second year of modern history for no reason becomes philosophy based subject matter. I never learnt anything about modern history in my final year of high school.
So while I thought I would learn about actual history of the past 200 years or so, I was instead being trained on how to be a "good little socialist"(tm).
You'll be glad to know I failed "modern history".
Although we did spend a month or so on the Vietnam War at one point, there was never any indepth study of that conflict, mostly brief study on the main events.
Luckily for me I was able to find a thick tome on the Vietnam War in the school library which was very indepth, and was written by the men who were there. Covered everything from "toe-poppers" to the jolly green giants, the native hill tribes enlisted by U.S. Green Berets et al, the recapturing of Hue after the Tet offensive, the Ho Chi Minh trail. Basically every aspect of that war.