This is a World War I song. World War I fascinates me because it was such a shock to the world. Nothing before or since has come close. It was a horrible, horrible event. It was modern weaponry and cavalry and then tanks. They fought for four years over a hundred yards, some ridiculously small amount of ground. It's the stupidest event in history.
This is one of those songs that I just can't sing - it's right in one of the cracks in my range. So we did it to approximate what a recording of that era would sound like. I know Mitchell's going to get blamed in some review for using all these effects, but we did it because I simply can't sing the thing.