We can find lots of resources and turn them into useful energy and things.
But that only exacerbates the pollution issue, regardless of where we obtain the resources. Especially noxious is the non biodegradable pollution and the millions of years worth of carbon released from the ground.
Factually untrue!
Obtaining resources on Earth generates pollution that stays on Earth. If we move mining off-world, the byproducts of mining don't go into streams, soil, etc.
Furthermore, generating energy in space and beaming it down to the planet means not having to burn coal, reducing the risk of nuclear accidents, and eliminating the need for dams that disrupt ecological systems.
Yes, we'll need to burn more fuel to get there, but that's the nature of progress. The other alternative is to fall back to a pre-industrial lifestyle limited to only those parts of the globe where the temperature is mild year-round - unless you want to keep burning wood for heat in the winter.
What, did you think there are no byproducts from operations done with raw resources AFTER they are mined?
And how about the mere transport of resources?
As for the Carbon - it doesnt matter how slowly we do it, we will still remove it all from the ground. It is a non renewable resource. Look at what we've done to slowly renewable resources like species - how many have gone extinct in the last 100 years? So yeah I think with carbon it's a foregone conclusion that we will floodthe atmosphere with it. But non biodegradable plastics etc. at least we can phase out.
And I understand the concern, but if reducing CO2 emissions is the goal, the first targets should be the production of electricity, heat, transport and agriculture. Food gets transported nowadays by airplane and maybe we shouldn't shut down nuclear power plants to replace them with coal plants. Plenty of low hanging fruits if you ask me.
Are you aware that advancements made for space exploration have helped the medical field? Things like NASA's digital image processing of the moon helping with MRIs and CAT scans. Or LVAD leading to artificial heart pumps. NASA is basically able to claim at least partial credit for things like ear thermometers, automatic insulin pumps, implantable heart defibrillators, improvements in digital mammography technology, programmable pacemakers, LEDs, etc.
The discussion is about mining and I see no reason for why space mining colonies couldn't be self-sustainable. If they cannot be, then space mining isn't feasible or too costly. And if they are self sustainable, then the fossil fuel mined and burned on earth would be worth it. If this was meant for me to feel shame of being alive and consuming carbon, take note that this is reductionist thinking, the same reason for why we find ourselves in the current predicament. Carbon emissions are only important as long as we have an impending global warming phenomenon potentially pushing us over a dangerous threshold. And while that's certainly a potential catastrophe, it's reductionist thinking in the sense that carbon emission isn't the real problem, just a reaction in a long chain of reactions and focusing just on carbon emissions will spell our doom.
But going back to your first question, we'd have plenty of water if we wouldn't pollute it, I don't see the need for mining decreasing, quite the contrary, so instead of dynamiting mountains and filling the area with cyanide for extracting gold or whatever, I'd rather have all of this happen in space, instead of our backyard. Mining on earth is only cheap because the costs are subsidized, being implicit in the damage to the environment, a cost that we'll pay sooner or later. If we'd factor in the real cost, if space mining is possible, I don't think it will look that expensive.