It could be colonies on the Moon or whatever. But I'm thinking a space-based industry to produce more space-based industry. If it could be self-sufficient, the question of "what does this do for Earth?" becomes moot. Like the Americas are not here to serve the old world.

Getting started, it could be a scheme of space development futures. Bet on the value of things in space, which puts money into the development of more things in space.

By 'in space' of course we mean everywhere in the Universe except tiny 'ol Earth.