I love the idea that humanity will become an interplanetary species, and that our descendants will be interstellar. The far future of life and the universe is a fascinating topic.

And I love how close it all feels now that we are in the Space Age, with rockets routinely headed to Mars and beyond, and humans once again primed to leave low Earth orbit for the first time in almost 50 years.

Elon Musk is riding this movement with audacious plans for things like a million people on Mars by 2050. His vision of human expansion is very different from Sagan’s—he’s explicitly a colonizer of space, selling a very throwback vision of domination of the cosmos by (some) humans. He even openly mocked Sagan’s Pale Blue Dot, where Sagan pointed out that there is no place—not even Mars—that humans can migrate to yet. Musk says yes we can too migrate to Mars now—as if putting a person on Mars is the same thing as humanity migrating there!

You see, “migrate” doesn’t mean “send a few people, maybe even permanently”. It means you pack up a huge fraction of people living somewhere and go somewhere else. Very different things. DNLee rightly asked whose “version of humanity is being targeted for saving?” when Musk speaks of those sorry souls that will remain “stuck here on Earth.”

Musk is getting a lot of justified criticism for his vision, and I especially liked Shannon Sitrone’s take on it (which included a quote I tweeted by Carl Sagan):

I have some thoughts about Elon’s desire to go to Mars and his laughing at Sagan’s Pale Blue Dot. My latest for ⁦@TheAtlantic⁩

Mars Is No Earth – The Atlantic https://t.co/YzaAKXimWn

— Shannon Stirone💀 (@shannonmstirone) February 26, 2021

Shannon takes on the trope that Mars is “Plan(et) B”, a way to escape Earth, pointing out that Mars is a terrible place to live. And it’s true! The worst winter night in Antarctica is a thousand times more habitable (and a million times easier to get to) than the best day Mars. And going there is not going to “save” anything on Earth, except incidentally via the technology we would need to live there.

Of course, the idea that humanity needs to become interstellar as a hedge against disaster makes sense, and if life on Earth has a future beyond about 500 million years, it will be in space, not on Earth. But acknowledging that is not the same thing as buying Musk’s vision for a million people on Mars in our lifetime.

After all, it’s hard to imagine any cataclysm on Earth that could possibly leave it less habitable than Mars short of something that destroyed everything on the surface—even the worst scenarios for climate change and nuclear war leave it with water, oxygen, one gee, and a biosphere.

Don’t get me wrong: there is a real, powerful vision for human migration into space, and I am excited to be alive to see it begin, but Musk is not doing the hardest parts of what needs to be done to make it happen.

“But SpaceX!” the Musk-ovites protest (and check out Shannon’s Twitter responses if you want to see how ugly the protest can get, especially when it’s woman criticizing Musk). And it’s true that SpaceX is amazing—I’m thrilled to see a new age of rocketry dawn with reusable rockets and a new philosophy that breaks the slow and expensive rut NASA and the rest of the aerospace industry has been stuck in. Tesla is amazing too—I look forward to owning one!

But there’s actually no contradiction here between criticizing Musk’s marketing and being impressed by and even in awe of the possibilities unlocked by the work of the engineers of the companies he owns.

To illustrate my point, think about weightlifting.

Getting into shape, especially building visible muscles, is a whole industry, an even mixture of science, engineering, medicine, biology, and psychology. If you want to be more Charles Atlas than 97 pound runt, there is a whole world of knowledge and a whole economy of trainers and equipment to help you get there.

If going to Mars is getting into shape in my analogy, who is Musk? To the Musk-ovites, he is some mix between Arnold Schwartzenegger and a cast member of The Biggest Loser: he’s the expert who will get us there.

But he’s not. He’s a BowFlex salesman.

https://www.youtube.com/watch?v=7odzT15-Rw8

Musk is the public face of SpaceX, which gets billions of our dollars (via taxes) to launch things into space. He has brilliantly built multiple companies using (among other assets) the force (I’d say cult) of his personality.

A million people on Mars is an amazing vision—especially if Mars has no extant life, it will be amazing when one day it happens.

But think about getting into shape: when someone needs to be in shape, like a professional athlete or an actor for a muscle-y role, what is the most important thing they do? Is it to buy a bunch of weights?

No! Not that they won’t need weights, of course, but in a pinch a sack of potatoes will do. What they mostly need is discipline, hard work, and a coach or trainer. The BowFlex equipment might make their training easier, but it’s neither necessary nor sufficient.

But you wouldn’t know that from the ads for exercise equipment and get-big-quick schemes, which promise if you just buy this thing you too can look like the models in the ads. This tactic goes back to Charles Atlas himself:

Atlas promises you the body of “The World’s Most Perfectly Developed Man…without weights, springs or pulleys. Only 15 minutes a day of pleasant practice—in the privacy of your own room.”

He’s basically selling a book of exercises you can do. Of course, knowing what exercises to do is important, but that’s not the hard part—the hard part is the training itself. But you don’t sell lots of books by promising hard work, you sell them with pictures of Charles Atlas.

To Musk, we’re the 97 pound runts “stuck on Earth,” and we want to be Charles Atlas up on Mars. Musk wants us to think he can get a million of us there by 2050 because he’s selling rockets.

But rockets aren’t the hard part!

We’ve been sending rockets to Mars for decades. Yes, his rockets are really cool and cheap, but also a BowFlex setup is much fancier and better than the weights Charles Atlas used to maintain his physique. And no matter how good BowFlex is, just buying it won’t make you Charles Atlas.

The hard parts of going to Mars are understanding how humans can live so long in space, and how to build (nearly) self-sufficient habitats with limited materials. We really don’t know how to do those things. Heck, we can’t even build a self-sufficient habitat in Arizona!

You don’t build a big physique in a day, and we can’t jump to Mars all at once. Musk wants you to think the stepping stones to Mars are bigger and bigger rockets, and maybe even a Moon base. But he says that because those things need rockets, and he’s selling rockets.  And it’s not right—we’ve already built Skylab and the International Space Station. We’ve already put things on the Martian surface.  Building a bigger rocket will certainly help, but it’s not the hard part.

The actual stepping stones are fully self-sufficient artificial biospheres on Earth and a better understanding of human physiology in low-gravity environments. When we can live in a fully-enclosed habitat Antarctica for years with limited or no resupply, I’ll believe we might be able to translate that technology to Mars.  When we understand enough about plant ecology to maintain a whole, closed ecosystem that can recycle enough oxygen for human use, I’ll believe Mars habitats have a chance. When people can spend more than a year or two in space and not suffer horrible physical degradation, I’ll believe humans might last on Mars.

And here’s the tell with Musk: he’s not solving those problems. He hasn’t bought Biosphere 2 to make it work, he’s not investing in the sorts of technologies you need to maintain human life in space. He’s taking a 1950’s sci-fi approach to the problem: send up more oxygen as needed, build bigger and better machines that will protect people, build bigger rockets to send it all to Mars. Because he’s selling rockets.

Like any good salesman Musk knows: don’t sell the steak, sell the sizzle. So when he talks, he doesn’t sell the rockets, he sells the things you could do with them, the same way a kitchen gadget salesperson sells delicious food or a perfume salesperson sells a beautiful lover.

But of course if those salespeople were really interested in you having those things, they’d be helping you with a lot more than food processors and aromatic oils. That’s how you can tell the difference. And Musk isn’t selling the hard part of space (the way Kennedy did for Apollo), he’s just selling the rockets.

Now, I know that by offering any criticism of Musk I’m inviting the Musk-ovites and trolls to come flame me (although I won’t get it as bad as Shannon does). So in case any of them have gotten this far, let me offer this:

It’s fine to be excited about SpaceX (I am!) and Tesla (I am!). It’s great to be excited about humanity’s future in space, and to help us get there. It’s reasonable to respect Musk for his entrepreneurship and success in business, and for his vision… just like it’s fine to admire Charles Atlas for his muscles and his marketing prowess.

But even the biggest Atlas fan can admit that his ads were making bodybuilding look easy when it’s actually hard. And even Musk fans can acknowledge that Musk’s salesmanship is just that: salesmanship, and that his vision of Mars that will take a lot more than he’s offering, and will probably need to change to accommodate the realities of Mars, humans, and ethics.

But there is a big contingent of super-fans that feels it’s important to publicly defend Musk against every criticism, to insist that his sales pitch is actually a complete and perfect vision of our best future, and that anyone who disagrees is somehow anti-space, or doesn’t understand the importance of space travel, or doesn’t appreciate how revolutionary SpaceX is. Musk carefully cultivates this kind of hero worship as part of his brand, and it creates a toxic atmosphere around the whole thing, hurting the whole cause.

I’ve had arguments with some of them on Twitter, some of them making, believing, and insisting on ridiculous claims like  “every prediction he has ever made has come true.” When I point out obvious counter-examples, they are brushed aside on technicalities. To them, Musk cannot fail, he can only be failed, and his critics are the enemies of the future of humanity.

Anyone serious about getting into shape knows about the whole world of advice and gadgetry, gyms and personal trainers, supplements and cuisines that surrounds the enterprise. Manufacturers like BowFlex are part of that and have helped a lot of people get into shape, and, yes, their sales force is an important part of that.

But think about how ridiculous you’d sound if you made one BowFlex salesman the first and last word on the entire subject?

If getting to Mars is really important to you, take a lesson from bodybuilders and go learn about all the pieces of that endeavor, and help humanity realize it. And don’t believe everything a salesman tells you, no matter how much you like his gadgets.

[Edit: It’s amazing how many Musk defenders will concede that we will not have a million humans on Mars by 2050 as Musk claimed, but still want to have arbitrarily long Twitter arguments to defend him against my accusation that his claims are unrealistic salesmanship.  Like, I said SpaceX is amazing and all, but Musk is overselling it. We agree!]