One of my earliest memories of revulsion against war came from seeing a photograph from the First World War when I was a teenager. It was nothing gory. Just a picture of a military officer, in an impressive uniform, talking to a puzzled and forlorn-looking old peasant woman with a cloth wrapped around her head.

He said simply: "Don't you understand, madam? The village is not there any more."

To many such people of that era, the village was the only world they knew. And to say that it had been destroyed in the carnage of war was to say that there was no way for them to go back home, that their whole world was gone.

Recently that image came back, in a wholly different context, while seeing pictures of American seniors carrying signs that read "Hands off my...