There is as much water per square mile on Mars as there is on the continents of our home world. - Robert Zubrin

Perhaps the question was premature in Turner's time, but not now. Currently we see around us an ever more apparent loss of vigor of our society: increasing fixity of the power structure and bureaucratization of all levels of life; impotence of political institutions to carry off great projects; the proliferation of regulations affecting all aspects of public, private, and commercial life; the spread of irrationalism; the banalization of popular culture; the loss of willingness by individuals to take risks, to fend for themselves or think for themselves; economic stagnation and decline; the deceleration of the rate of technological innovation. . . . Everywhere you look, the writing is on the wall. Without

Perhaps the question was premature in Turner's time, but not now. Currently we see around us an ever more apparent loss of vigor of our society: increasing fixity of the power structure and bureaucratization of all levels of life; impotence of political institutions to carry off great projects; the proliferation of regulations affecting all aspects of public, private, and commercial life; the spread of irrationalism; the banalization of popular culture; the loss of willingness by individuals to take risks, to fend for themselves or think for themselves; economic stagnation and decline; the deceleration of the rate of technological innovation. . . . Everywhere you look, the writing is on the wall.

According to advocates, such as Princeton professor Gerard O'Neill, such commerce could then provide the economic foundation for the development of large colonies, literally cities in space, in high Earth orbits, and this vision has served to motivate many space entrepreneurs, notably Blue Origin founder Jeff Bezos.