Do we really need these big, gigantic, heavy rockets? What if we launch a rocket that's empty, and its sole purpose is to act as a source of fuel on the Moon? Who should build that? Well, I think the U.S. should build that.

Returning to the Moon with NASA astronauts is not the best usage of our resources. Because OUR resources should be directed to outward, beyond-the-moon, to establishing habitation and laboratories on the surface of Mars that can be built, assembled, from the close-by moons of Mars.

I think we need to move to the moons of Mars and learn how to control robots that are on the surface. It's not the impatient way of getting there, but Mars has been there a long time.

Unless we are able to commit to a permanent growing settlement [on Mars], then I don't think just going there with humans and coming back is worth doing. The expense of planning to come back is like the people who left Europe to come to America and then to turn around and go back to Europe, it really doesn't make any sense at all.

Exploring Mars is a far different venture from Apollo expeditions to the moon; it necessitates leaving our home planet on lengthy missions with a constrained return capability.

I really hate to be put in the position of trying to justify something, a decision that was made. I'm a military guy: when a decision is made, I go along with it, whatever the manufactured controversy and criticism.

Not everyone will understand this need for America to lead the world in space.