Here’s the thing: it is probably possible, given enough investment, to get a self sustaining civilization in space started. But it wouldn’t necessarily help th

Here’s the thing: it is probably possible, given enough investment, to get a self sustaining civilization in space started. But it wouldn’t necessarily help the people still on earth very much. Take any island nation: Iceland for example. They have a small population so they can’t make everything they need; they import lumber, cars, food, etc. And they always have, right from day 1 that the island was settled. In space however the cost of constantly lifting goods from earth is too high to do that forever. So they have to be totally self sufficient. That means manufacturing, energy, extraction of minerals from asteroids, everything has to be in place. I’d say minimum 10 million population before they can assemble the diversity of industries to do that. Once they are at that point though, what are they going to trade with earth? Any minerals they obtain will be better used in space then parachuting them down to the surface for processing. So they wouldn’t need us at all. So it’s possible but politically very difficult to justify.