> absence of self-sustaining colonies in harsh outposts on the earth (and similar absence of more local positive terraforming projects) indicate limits in how serious anyone is about colonizing Mars
This is a stronger argument. I agree. I think there is serious interest in establishing permanent facilities on Mars. But a self-sufficient, self-sustaining population isn't being planned on because there are too many unknowns for any definition of a plan that doesn't overlap hard science fiction.
Something I've never even seen mentioned, let along seriously discussed, is the protocol for deciding under what circumstances the first human will be born and raised off-earth. I predict that will turn out to be an intractable problem.
Oh, you're talking about extraterrestrial reproduction being intractable. Sure. I have no view on this scientifically. That won't stop people from trying. And I'd assume there's a massive difference between zero g and 0.4g.
This is a stronger argument. I agree. I think there is serious interest in establishing permanent facilities on Mars. But a self-sufficient, self-sustaining population isn't being planned on because there are too many unknowns for any definition of a plan that doesn't overlap hard science fiction.