My friend Charlie keeps up with World War II history documentaries and books. Recently he told me about the documentary "The Ghost Army." I believe he caught it on Netflix. I found it on Amazon Prime.
If you are interested in art, sketching, or what happened in WW II you need to see this video. You'll see how the 1100 American G.I.s of the 23rd Headquarters Special Troups, known as the Ghost Army, fought the war by artfully creating fake convoys, phantom divisions, phoney radio broadcasts—in short put themselves at risk to practice deception and confuse the Germany forces.
You'll also see the wonderful sketches and paintings these men, many of whom were recruited from art schools, created during quiet moments, and not so quiet moments. You may also be surprised to learn how many of these young men went on to have careers in art. (I won't spoilt it by listing them in case you don't know.)
This is a short, wonderfully produced documentary that you must watch.
After watching it I went in search of a book containing all the art I'd seen in the film. I found "Artists of Deception: The Ghost Army of World War II" which is a 48-page catalog for the Ghost Army museum exhibit. Unfortunately all my favorite sketches from the film are not included here, but there is enough great stuff that I'm really glad I have the book. It makes a nice reminder. I guess I'll have to buy the DVD too!
If you think your sketch adventures are intrepid, or fraught with obstacles you need a wake up call. This is extreme field sketching beyond your imagination, a grueling sketch out like no other; with the artists doing what they always do—looking closely to observe their world. The documentary is also a very clear answer to "why draw?"