Asklemmy

I don’t think space habitats any significant distance from Earth will be possible. Mitigating the increased radiation will be tough enough just trying to get to Mars, much less trying to stay in space out that far. At least on Mars we can hang out in old lava tubes or something.

A quote attributed to a few people, Heinlein and Pournelle for two, "If you can get your ship into orbit, you're halfway to anywhere." Both space and planets have shared and their separate problems to solve. In my head I prefer the image of most populations moving into habitats in space, customized to their preferences, with smaller settlements on various bodies for their own purposes. In my realistic view I don't see us getting that far before we get bogged down with all the problems we've created on this planet. The window to a permanent space civilization might have already shut. A sad thing, as a 70s kid I grew up convinced we were full speed into some version of what scifi had sold to me.

After reading A City on Mars by Kelly and Zach Weinersmith I think a O'Neill Cylinder spinning spaceship for artificial gravity type is more achievable than planarity colonisation.

But the main point of the book, and I am fairly convinced of the more I think about it, is that it is a lot of effort and risk for not a lot of gain and we are entirely unprepared for space colonisation.

All of the above. But start with cleaning up this planet. Build better / more sustainable and more diverse communities and energy production. Build arcologies in the arctic, deserts, oceans. Those are good “practice” for building the same off planet.

Yes.

Seriously, we should be doing both as long term space habitats can serve as a way to reduce the cost of moving cargo around.

Why not both?

I'm guessing B will happen first, just because we have so much more control of the environment, but we're still so far away from either one... Maybe I'll get to see the early stages sometime in my life.

What’s the purpose—research? Tax evasion? Shits and giggles?

D) Move manufacturing and other dirty processes off planet and live here.

C) keep the planet we have habitable

yes.

if we want to become a true space faring species resilient to all that the universe can throw at us we will need both