Absolutely the United States should lead in space, for the survival of the United States. It's inspiring for the next generation. If we lose leadership, then we'll be using Chinese capability to inspire Americans.
You can never tell when a commercial space venture will suddenly become viable.
In space, you don't get that much noise. Noise doesn't propagate in a vacuum.
To move forward, what's required is a unified space agenda based on exploration, science, development, commerce, and security.
Most people never believed in the real possibility of going to the moon, and neither did I until I was in my twenties.
The decision to go to the moon is now appreciated and associated with President Kennedy's speech, but somebody else had told him it was a good idea. It turned out to be a good commitment, but it was a unique situation.