A simple - and, I gather, mostly true - story from World War One. French General Mireau (Macready) orders a suicidal attack on a well-guarded German position. Mireau, of course, isn't blamed for the subsequent failure. Instead, three of the soldiers who managed to survive are "made an example of" and put on trial for their life, under the vague charge of "cowardice". Colonel Dax (Douglas) defends them.
This has been described as one of the greatest anti-war movies of all time. I don't see it myself. The generals of the WW1 French army come across as corrupt, cowardly and inept - which is why Kubrick wasn't allowed to film in France - but the film isn't really saying anything about war in general, apart from the fact that it's a good deal more horrible than the French generals in their cosy chalet imagine it to be, which is only to be expected, because the French generals are idiots.
I saw the film on video, and it was clear I wasn't getting the full effect. Kubrick's images are almost always stunning, but the picture I saw had been so obviously cropped for a TV screen, it was embarrassing. If you plan to see the film at all you should certainly see it now.