Love this article, Matthew. I couldn’t agree with you more, both in your general attitude toward the development of space and your point that our ability to “get at” resources that are already out there will be critical. I’ll add that in addition to your hydrogen/oxygen rocket fuel, they’ve also noted that for Mars-based activities methane will probably be the way to go — it can be produced from Mar’s CO2-rich atmosphere.
Most of the time on Earth we regard water as water, not as hydrogen and oxygen. It takes energy, and a fair bit of it, to separate water into its components. This generally defeats the point of then burning the hydrogen and oxygen to produce energy — the round trip winds up costing us net energy. But it’s important to note that in space we basically have all the energy we need, because of the abundance of solar energy. So it makes a lot of sense to use that energy to produce something that can give us energy in a way that sunlight can’t. We can use sunlight directly to propel spacecraft (solar sails), but only at very low thrust. If we use it instead to separate water into H2 and O2 and then use that as a rocket fuel, we get a lot of thrust. And the energy is essentially free, so that’s a win.
We already have (and have had for decades) at least one basic blueprint for sound habitats in space. Gerard O’Neill gave us excellent plans for habitats at L4 or L5 back in the 1970’s. Such habitats will cost us MUCH less if we build them from materials already in space, rather than from resources launched from Earth.
I have high hopes for the future in this area. I think we truly do stand on the brink of becoming a space-faring, multi-planetary society. It could potentially happen in our lifetimes — if Musk’s plans come off even 3/4 as well as he’s hoping we will live to see permanent Martian habitation. It’s an exciting time to be alive — that first permanent step into space will forever be one of the most significant moments in human history.