Have movies taught us anything truthful about war?

I think most films, at least American, have glorified war, though I have seen exceptions:

All Quiet on the Western Front (1930) is to me a powerful meditation on war because it presents to American audiences the face of the German soldier as hero (or at least protagonist). Its moral issues/ ambiguities are uncompromising and strongly anti-war.

And although I wouldn't say the rest of it is much better than most of the conventional war films that came before it, the first twenty-minutes of Saving Private Ryan (1998) are as harrowing and as powerful as any war scenes in cinema. When I saw it, I sat next to a female documentary filmmaker who had emigrated to America from Europe not long after WWII. We'd only met only a short time before, but during those opening moments she held my hand and cried. I don't know how anyone watching those extraordinary images could fail to see that war is insane.

Same with Rome, Open City (1944) The final moments of that film are haunting, because they convey the utter capriciousness of war. Death comes in a flash, like nature, "long in tooth and claw," and there's no escape from it. I learned from that film that the most devastating truth of war is not so much that it's immoral, but that it's AMORAL, against which there's no defense.

And, in a slightly different vein, I was powerfully affected by sixties' films like Petulia (1968) dramas that played out against the drone of the Viet Nam war on background tvs and radios, a constant reminder of the human cost of political hubris. I do think those messages penetrated, at least subliminally, the consciousness of the American culture at the time.