The Guns of August is a great book. I read it and followed up with Dan Clark's Great War podcast.
I was just like you, waving the flag and thumping my chest. I gained so much from the service but I lost a lot as well. Lost some good friends, got a nice case of PTSD to keep me company.
It's bullshit like you say. So much wasted.
I'm going back and forth between it and Joan of Arc by Mark Twain. Mark Twain said it was his best book. I think he researched it for over two years and I think it took him over a year to write it.