The same thing we do here I guess.

There is enough material wealth in the asteroid belt to create a sustainable post-scarcity civilization. We could move out, and turn this little blue-green planet into a fucking nature preserve.

Settlements on multiple worlds within the solar system offer protection against risks that might otherwise end with the extinction of Homo Sapiens.

For the ultra rich - moving off world to escape the collapse of the biosphere is ridiculous.

Easier to “settle” the deserts of Utah of the Australian Outback than Mars - plenty of O2 and no worries about ambient radiation, but a very similar environment…

The idealistic answer: Science! Lots of things to learn by establishing humanity’s first extraterrestrial presence on our closest celestial neighbor.

The realistic answer: Capitalism. Lots of money to be made in mining the moon.

I’d separate this into two different things - what is good for humanity and what is good for billionaires like Musk.

For humanity, venturing out into the solar system will advance science, and also help drive technological advancement which does have benefits for society as a whole. The space race in the 20th century did advance technology, and much of the modern technology we take for granted has routes in the space race.

But also humanity needs to move away from our current capitalistic system and that is very much driven by scarcity. The resource wealth in the solar system is mind bogglingly vast and if we can tap into even a portion of it, it could allow us to change how we as a species live. It would initially be driven by capitalism for sure, but when you have effectively infinite resources for a civilization, that changes everything we do.

Also for the long term survival of our species we need to be looking outwards. Earth is vulnerable - one asteroid strike and out species could be wiped out. Even if only a small number of people were to head out into the stars, it would help guarantee a long term future and resilience for our species.

I think one big mistake people make is that what happens on earth is a zero-sum game: i.e. for some to win, it must be at the cost of others. That is wrong and is a result of our terribly broken economic system. But we can both colonize the moon and mars AND fix the problems on Earth. And it may do good for our species to look up to the stars and have a bigger shared goal than just existing on this rock and acquiring wealth.

In terms of why the moon & mars. The moon is essential as a staging post for future expansion, as it’s very expensive resource and energy wise to launch from Earths gravity well, but much cheaper to build at the moon and launce from there without the added step & complexity in design for launching off Earths surface. Mars meanwhile is the most viable candidate at present for a self sustaining colony long term (with a couple of moons of Jupiter and Saturn other options, and possibly venus as a long stretch).

Meanwhile, Musk is a deranged billionaire idiot. He is nothing more than a investor gambler; other people are doing the hard work making things happen while he is a public face of various companies. He really is peripheral to this, even if he does push the topic into the public consciousness. Don’t conflate the idea of expanding into the solar system with that idiot. The idea precedes him and will run long beyond his life and any influence he has. He is just a narcissistic loud mouth with money.

In the case of musk and his billionaire friends, they just want to escape the consequences of their actions and become above the law. Basically they want to be a king, with no laws restraining them.

The moon is a great starting point to explore the rest of the solar system, doubly so if we found water on it.

I’ll quote JFK (probably more Ted Sorensen) on this one « we don’t do this things because they are easy but because they are hard […] »

people love the dream/myth of cutting their old lives free and moving away to start a new one. this is that dream writ large for megalomaniacs who have already run as far as they can from the people they’ve hurt and from themselves.

What better place to do all of the dirty work like mining and refining from asteroids that have a ton of metals and resources, then just send the finished product down to earth. No more mining our unique and delicate planet and polluting it.

Musk believes in a sort of secular mormonism except instead of magic he has money so he tries to eventually, after millenia to spread his progeny over the entire known universe

Putting bases on the Moon means we can do more studies, experiments, etc. outside of Earth, particularly tasks that are difficult to complete by current rovers. Human physiology in low gravity situations, lunar geology, possibility of water and life outside of Earth, that sort of stuff. I’ll also echo what others have said about how the Moon could become a launching base for future explorations, given its lower gravity and lack of an atmosphere.

There isn’t a conspiracy by lizard men to set up a Death Star, this is driven by the curiosity of humanity and our desire to explore the unknown. The “race” to have the first base between Americans and Chinese is, like during the Cold War between the former and the Soviets, a push to be the first, trying to show that they are ahead in terms of technology and science. In a nutshell, it’s driven by curiosity and, at least partly, national pride.

Oh you know, just the kind of things they do on remote privately owned islands.

Other people have made solid points, but one thing I think people miss a lot of the time is that “because it’s cool” is a good reason in its own right.

I could argue almost any endeavor that isn’t actively feeding the poor is a waste of resources. Oh, you’re making art? Why aren’t you working in a soup kitchen instead. Oh, you’re building a monument celebrating a civil rights victory? Why not a homeless shelter? Literally any end that isn’t active altruism can be attacked as “why are you wasting time on that.”

But one of the best things about living in organized society is that we can pool our collective resources to do awesome stuff that otherwise wouldn’t be possible. It’s good that there are wonders in the world. I’m glad the pyramids exist. I’m glad the Taj Mahal exists. The Eiffle Tower. The Statue of Liberty. It’s amazing what people can do.

And sure, that money, time, and energy could have gone to helping the poor. And sure, none of those were made in a society without significant social problems.

But we can walk and chew bubble gum at the same time. And the fact that the poor exist shouldn’t stop us from doing cool things. Even if they don’t have immediate and apparent “value.” I don’t have an MBA. I’m not looking to maximize shareholder value. And I’m all on board with doing cool stuff, even if it doesn’t have a positive ROI.

I’m getting more cynical as I get older, I witnessed the moon landings when I was young and I was thrilled. Humans are not made to live in, or to travel though space. Space, with its vacuum and high radiation levels is extremely unwelcoming. We better stay on Earth and fix our beautiful planet! But, it is again a space race, if NASA or Bezos or musk don’t get there first, the Chinese might. OMG! The Chinese! So we invent a lot of reasons why humans must live on the moon or mars - whereas our robots are doing a pretty good job in exploring these planets or the universe.

We need the Helium-3 from the moon.

For the billionaires talking about future settlements on Mars and the like, there isn’t a short term benefit to actually doing it. That’s why they aren’t investing heavily in realistic plans to colonize the solar system. They are investing in space, but in a much more limited capacity that mostly involves satellites, government contracts and maybe a little space tourism for rich people.

All the talk of taking humanity to other worlds is good PR, inflates stock prices, and feeds into their own egos. It’s a way of projecting the image of being a visionary and being able to claim that they’re building a brighter future for humanity, and taking credit for making sci-fi pipe dreams a reality.

There are potentially massive benefits to spreading out in the solar system. We currently have access to a single planet’s resources, and Earth didn’t vacuum up all the useful materials in the solar system when it formed. There are also resources which are more abundant in space like helium-3.

But that’s all long term stuff. We may eventually build a moon base that refuels ships which support asteroid mining operations, send robots to build industrial complexes on Mars, and even start the long process of terraforming Venus so that one day we can have a second habitable planet. But first we have to get to the point where just getting into space isn’t so monstrously expensive.

And even if we had a working space elevator tomorrow, there would still be a ton of technical hurdles to overcome before we could accomplish something new that actually helps pay for all of this stuff. There’s speculation and research, but don’t expect massive investments until we’re almost there. Once independent researchers and unrelated technological advances have solved 90% of the problems and it looks like there will soon be trillions of dollars to be made by whoever capitalizes on it first, then you can expect the irrational gold rush moment like the one we see with AI now. Until then, it’s all satellites and stock manipulation.