The Arsonist
A footnote and counterpoint to Harry and his state of mind would be the arsonist. He's about the same age as Harry, same generation, but apparantly has none of the angst or despair that Harry is experiencing.
He's good at his work and proud of it. He sees himself as a skilled professional and a craftsman, and he has ethics. He returned the deposit to Harry when he thought he couldn't do the job. It was important to him to produce a quality product for his customers, just like any good businessman.
Of course the irony is that he's a criminal, and his role in the film is to help destroy (with Harry's cooperation) what Harry has built. It's possible that he represents the destructive forces that are destroying the America that Harry knew and loved.
Stacy - We got a job
Uncle John - What kind?
Stacy - The Forever Kind...