> Where are you going to get that, or any other raw material?
Bootstrap with whatever the initial mission payload is. It's not like anyone is proposing magically teleporting there without stuff, IIRC even Musk's optimistic idea is still several no-humans flights for each passenger flight.
> Robot miners? We don't have those on Earth yet.
Sure we do. TBMs. Not all of which are manned. A few of the missions on Mars right now are taking rock samples with drills.
(Honestly, I'm mainly thinking of the moon, but Mars has moons too. No idea if any of Mars, Demios, or Phobos have significant easy access to aluminium oxides).
> Where do you get the power for all of this? Solar panels don't behave well during sandstorms, the sun isn't very bright there, and how many solar panels can we really fly to Mars?
Sure, PV. They do suffer as you say, but that's not a critical failure when bootstrapping a colony or whatever, especially when you're in the "robotic labor only" phase that (a) is a prerequisite and (b) Optimus Prime or whatever random pop culture reference Musk named that middling demo after. While I don't have any reason to actually trust Musk's "million people" number as anything more than a nice round number, at that kind of scale you necessarily have a lot of PV. Like, "tens of square km" is the minimum baseline. How much is made locally vs sent by Starship depends what can be made locally vs. what can't.
Plus, a Mars colony is one of the few situations where orbital solar via microwave isn't obviously worse than "a big wire to the other side of the planet".
As Starship has ~100T payload, and this PV is 120 W from 5.2g, given 50% reduction in sunlight relative to Earth, even if all the semiconductors have to be shipped from Earth, it's only a few flights out of what you need just to get the people, never mind the other bootstrap equipment you also want: https://spectrum.ieee.org/ultrathin-solar-cells-for-lightwei...