> On a per-capita basis, in advanced economies, it's been flat in several categories.

Right, but our population is, at this time, growing exponentially. That may change but hasn't yet.

> If anything, the constraints of spacefaring seem perfect for nudging a culture and economy towards conservation and recycling.

Quite possibly! I agree. But what I was saying is that getting access to resources does not solve sustainability. If anything this is an argument that sustainability is a prerequisite for space travel and not the other way around.

> Nobody is banking on space-based resource extraction.

I understand this is not your position, and I appreciate that your position is reasonable and informed. But it is what was being discussed when you joined the conversation. And it is something I hear people say all the time.

Specifically, this is what I was responding to: https://news.ycombinator.com/item?id=46563421

> [Which] do you think is going to get there first?

Are these hypothetical civilizations on the brink of unlocking space travel? Or are they 100 years away? The civilization hell bent on space is likely to burn themselves out and replace their leadership with people with more grounded ideas if unlocking space travel isn't a realistic possibility for them. If space travel is right around the corner than my expectation would be the grounded civilization freaks out about national security and joins this space race in earnest. I think in either scenario, all else equal, it's a coin flip. The tortoise and the hare both have viable strategies given the right conditions.

This is kinda sorta what happened in the space race. The USSR pursued rockets aggressively and took a massive early lead, believing that ICBMs were the solution the the USA's dominance in bomber aircraft. But they couldn't sustain that pace. If I recall correctly, by the time we landed on the moon they hadn't launched a mission in years. The USA more or less gave up on manned space travel and space colonization shortly thereafter. Obviously both continued to explore space and the tide is beginning to change, but I think that's a natural experiment which roughly addresses this question. (Not to the exclusion of future attempts with better technology going better.)

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