'this woman was in her 40's, so in the early 90's when everything was happening and he was all over the news she would have been in her 20's. So not really even history, just general knowledge I suppose. How could she have missed it? '
The idea that something would have been all over the news in the US is where you're going wrong. American commercial media in the late 80s and early 90s was appalling -- coverage of major events like the fall of Communism was a joke, and the internet was only really in its infancy at that time.
Historically, though, the US has not really had any ties to SA, and events there would not have resonated in the way they did in the UK; the African American community felt more connected to the end of apartheid than the majority, but the media tends not to reflect the preoccupations of the minority. There was absolutely no excuse for the woeful treatment of events in Europe however.
In defense of American history education, I was very impressed by the courses taught at DD1's US high school and the level at which they were taught. She studied World history, American history (AP course) and Middle Eastern history. However, not all students took these courses, except for World history which was a graduation requirement in her school, and of course it is up to each individual student to actually learn something in any given class.
FlorenceCalamnty -- I have to say I agree with your post about British lack of knowledge when it comes to Ireland; mind you I think the same could equally apply to Ireland. I don't know if my primary school was the exception but I never learned a single detail about British geography in school, while I could name every single major river, mountain range, city, port, railway junction, source of various raw materials and large industrial area of mainland Europe (western Europe at any rate). Primary school history started with the Iron Age and ended in 1916, so it definitely had a theme of the Irish colonial experience and 'struggle for freedom' in the later years, with references to the wider world thrown in as needed to explain Irish events. Modern European history for the Inter Cert and Leaving had a decent curriculum though.