Very educational. Thanks for posting.
ETA: My grandfather fought in WWI as part of the US Army Artillery. I'll need to read all of his letters back home next time I visit my folks. He never talked about the war when we visited in my youth. The last time I read one letter, I found it interesting that he was discussing fighting "the Hun" and referencing General Pershing. I really only knew the name "Pershing" as a missile in my lifetime.