Is the surface of a planet really the right place for expanding technological civilization? - Gerard K. O'Neill

There's no point in going out into space if the future that we'll see there is a sterile future living in tin cans. We have to able to recreate in space habitats which are as beautiful as earth-like as the loveliest parts of planet Earth and we can do that.

We should ask, critically and with appeal to the numbers, whether the best site for a growing advancing industrial society is Earth, the Moon, Mars, some other planet, or somewhere else entirely. Surprisingly, the answer will be inescapable — the best site is "somewhere else entirely."

Clearly our first task is to use the material wealth of space to solve the urgent problems we now face on Earth: to bring the poverty-stricken segments of the world up to a decent living standard, without recourse to war or punitive action against those already in material comfort; to provide for a maturing civilization the basic energy vital to its survival.