It's not just the USA. Here in Finland I was pretty much only taught how the war started and how it affected Finland (which gained independence from Russia in 1

It's not just the USA. Here in Finland I was pretty much only taught how the war started and how it affected Finland (which gained independence from Russia in 1917, and then fought a civil war in 1918 with some involvement from Russia and Germany). My teacher openly told us that we don't need to know any details about ww1, since ww2 is much more important (although the teaching about that one also emphasized the Finnish wars (winter war, continuation war and Lapland war) more than the ww2 itself).