It’s all in DeNiro’s eyes...the movie is about the passage of time for a working man who was not above using a high degree of violence, to make a better life for his family. It seems to be about America-about the Kennedys, about Jimmy Hoffa, about the dehumanizing effects of war in the way soldiers learn to cope with stress and orchestrate violence.
It is also about the emptiness and waste that awaits from a lust for privilege and power. Or literally death in the form of bloody and brutal murder.
As with all of Scorsese’s best movies, he never judges his characters-he observes them and lets the audience reach a conclusion about their virtue (or complete lack of it).