I highly recommend two movies about war. The first is "Before the Rain," a Macedonian movie somewhat in the style of the French Blue, White & Red series. The second movie is "Ida," a Polish movie about the after-effects of WWII. Both are in the very top tier of movies. Both do not remotely glorify war, not even one iota. It is impossible to imagine someone would watch either movie and have even the faintest desire to join a war or be in any way associated with a war.
The short story collection, "Redeployment," by Phil Klay, is also worth reading. Phil Klay was a Marine, and the short stories are about Marines in Iraq. The stories are well-written, gritty, insightful, and really depressing. Any piece of art that's about war and isn't really depressing is highly suspect.