can spacex really build a martian metropolis?

Just how realistic is Elon Musk's 80,000 person outpost on Mars given enough time and money?

Whatever you do, don't say that Elon Musk isn't ambitious. While most Silicon Valley bigwigs try to sell us on some new app they always promise will change the world as we know it and larding their pitch with buzzwords like "social," "cloud-ready," and "disruption," he put his resources into a craft able to resupply the ISS and is busily planning what could only be described as a city of 80,000 people on Mars. How does he think this would happen? First, make his rockets reusable so they can be cleaned up and ready for their next launch in a matter of days. Second, using space tourism to create the economies of scale necessary to cut the cost of traveling to Mars to just about $500,000 or so. But while reusable spacecraft and economies of scale will go a long way, would they really encourage a mass migration of tens of thousands of people to a hostile alien world with immense dust storms, non-negligible radiation hazards, and a distinct lack of the few basic things they'll need to survive outside of their little environmental bubble?

If SpaceX wants a Martian city, it will need to cut the trip time down from 8 months and make the flight itself a lot safer and a lot more comfortable than in an Apollo-style capsule. It would have to essentially set up something much like a space station which would travel between our planets, ferrying passengers back and forth, powering it and its engines with nuclear reactors. That's not an easy task, both from engineering and legal standpoints, though the latter could pose far more of a problem than the former considering the history of the Outer Space Treaty. And while I can certainly see adventurous billionaires and scientific agencies shelling out even $50 million for a ticket to Mars, does SpaceX really think it can maintain a population of 80,000 people who would expect creature comforts and will have to be constantly supervised to ensure that exposure to alien gravity and radiation for months on end doesn't leave them incapable of ever setting foot on Earth again? Sounds like Musk would have his hands full.

Finally, here's another issue to consider. What exactly would this city provide from an economic standpoint to justify its existence? There are only so many tourists and so many scientists. While it certainly does make sense to set up a Martian habitat, a population goal of 80,000 might be a little too ambitious to be workable and the habitat is unlikely to be economically self-sustaining if we consider how remote it will be and how difficult it will be to maintain. I can certainly see why Musk would want to shoot for something like this and definitely appreciate doing science for the sake of science. But after a certain limit, something like a city or a research base would have to give companies reasons to invest in it, otherwise, it will quickly either run out of funding or work and be abandoned. Take the ISS for example. After tens of billions of dollars and decades upon decades of work, it's finally completed. Only to be understaffed and underutilized, kept alive by space agencies trying to justify the project that'll never be what it was meant to become. I hope that Musk takes the ISS' example to heart and avoids making the same mistake…