A human tragedy. Melancholy, Dark, filled with "unawareness." People don't seem to think about their lives or actions....except for Sheehan's daughter, Peggy.
One thought-provoking scene is when Sheehan is a soldier and is standing over two prisoners of war who are digging their own graves. They come up out of the pit and stand near the edge looking directly at him. He apparently follows orders and shoots them. They fall into the pit they'd dug for themselves. This is the beginning of his ability to kill. ....a warning against the effects of war.
I thought the end of the film, with everyone aging, was the perfect finale for this story. This is definitely a morality play about what matters in the end. All of that effort, murder, energy.....for what?