Easy come, easy go. The United States worked hard to put people in the moon in the 1960s. Then, after achieving the goal with more landings over three years, we left in 1972 and have not been back since.
, a geologist and lunar scientist, thinks it's time we returned. In , he makes the case for using the moon, both for its location outside of near-Earth orbit, and for its resources. He explains what those resources are in his book and in a visit to The Exchange.