Whoever manages the feat, whether it's Elon, the Chinese, or some other enterprise, establishing a colony on Mars will be a money losing situation for decades, if not centuries. And by losing money I mean many billions of dollars, possibly trillions, for the reward of bupkis. Oh sure there will be research value, but not trillions of dollars' worth. There is also the trope that we need to establish an off earth populace to distribute our eggs into more than one basket. Cogent sentiment, but there are just too many problems to overcome.
First is getting there and back again. With current, or even foreseeable, technology the route between Mars and earth will be absurdly time consuming. And there will have to be a lot of trips back and forth to support more than a handful of people for long periods. Need a critical part for some machinery? It'll be an absolute minimum of six months before that part will arrive. And it could easily be twice that long, or more, if the orbital mechanics of the trip are unfavorable. Mars and earth spend considerable parts of a year on different sides of the sun.
Unless spacecraft propulsion takes a huge leap forward in the next few years, and it shows no sign of doing so, lengthy travel times will be unavoidable. A hyper-advanced nuclear propulsion will be required to significantly shorten transit times. And you can be certain that such propulsion systems will be hideously expensive to field. And even if by some miracle the tech is reasonably priced, it might only shorten transit times by a few weeks, if that. It could be that E.M has an advanced propulsion system already in hand and is keeping a lid on the tech until the time is right to spring it on the public. I wouldn't bet good money on that scenario though.
Speaking of money, it's going to take a bottomless barrel of it to make all of that possible. The ROE?Negatory good buddy. E.M. could spend every last dime on the enterprise without even the ghost of a positive return. My sense is that a monstrous negative return is likely well into the next century, if not. the century after that. And anyone hitching their wagon to M.'s starship will see the same return, nada. The prospects of a Mars colony being entirely self-sufficient are very dim indeed and will hardly be attractive to even the most altruistic gazillonaire.
Altruism, even E.M.s, has its limits. "Capitalists!" I hear you sneer, as if trillionaires are nonchalant about sinking hundreds of billions into an enterprise that won't really benefit anyone in the near term, or long term for that matter. The same goes for the moon despite how long moon colonies have been a common trope of science fiction.
At least the travel times to the moon are manageable, and communications will only lag a few seconds instead of several minutes for Mars. But, Mars and the moon have a common problem in that surface gravity on Mars is one third that of earth and the moon is only one sixth. Spend years on the moon or Mars and you'll no longer be capable of tolerating earth gravity. And we have yet to determine how that much lower gravity will affect the body after years or decades. That simply can't be determined without putting people on both Mars and the moon for decades. It's just too complex a problem to solve by simulation. In short, a Mars colony is a pipe dream, and the pipe doesn't have tobacco in it. At least until someone invents artificial gravity. Don't wait up.
