Some stories​ are so well known in outline that we don’t really know them at all. The headline news about the Wright brothers’ invention of powered flight is so familiar that it’s easy to think we know all about it. David McCullough’s excellent biography The Wright Brothers brings the story back to life with facts that the non-specialist either doesn’t know or has blotted out with a misplaced broad brush. Yeah yeah, we get it: the brothers were provincial tinkerers who first flew their invention at Kitty Hawk, then became world-famous. It turns out, though, that there is a lot of devil in the details.

The tinkering, for instance. The Wrights were pioneers in the cycling business who ran a bicycle shop in Dayton, Ohio. Wilbur was born in 1867 and Orville in 1871. They were an unusually close pair who all their lives lived together, worked together, ate together and shared a joint bank account. (McCullough is too respectful of their boundaries to say so, but it seems likely that they were both lifelong virgins.) One of the only things they didn’t do together was fly: that would have been too much of a risk to the irreplaceable knowledge they’d jointly accumulated. Their father, Milton, was a bishop in the United Brethren Church who accepted his sons’ lack of faith with equanimity, and was going on suffragettes’ marches with his only daughter, Katherine, in his eighties. Katherine, a teacher, was the only family member to go to university, and the only sibling to have consummated a relationship, marrying at the age of 52.

‘It isn’t true,’ Wilbur later wrote, ‘to say we had no special advantages … the greatest thing in our favour was growing up in a family where there was always much encouragement to intellectual curiosity.’ Wilbur’s interest in flight began in childhood; it turned into an obsession and then into a practical plan. Other pioneers of flight were focused on the question of power. The Wrights were fascinated by birds, and learned a lot from their study of them. One of Wilbur’s crucial insights was that flying, like cycling, was a question of balance. He saw that bird flight was all about equilibrium: about the bird’s keeping itself in the air with the maximum efficiency and minimum effort.

It followed from this that the first step to flying was gliding: building a craft that could stay up in the air as long as possible. That meant finding somewhere windy, because the flow of air over a wing is what creates lift. A steady source of wind is the would-be glider’s friend. Wilbur wrote to the US Weather Bureau, which sent him data on wind velocities in more than a hundred places. One spot stood out: a community called Kitty Hawk, seven hundred miles from Dayton, on a chain of islands and sandbars off North Carolina known as the Grand Banks. Wilbur wrote to the head of the Weather Bureau station on Kitty Hawk and had a letter back from the former postmaster, Bill Tate, who was to become a good friend and helper to the brothers. The issue wasn’t only the wind but the ground: the prospective flyers wanted a mixture of terrain, ideally with firmish ground from which to launch and softish on which to land.

In answering I would say that you would find here nearly any type of ground you could wish: you could, for instance, get a stretch of sandy land one mile by five with a bare hill in centre 80 feet high, not a tree or bush anywhere to break the evenness of the wind current. This in my opinion would be a fine place; our winds are always steady, generally from 10 to 20 miles velocity per hour.

So Kitty Hawk it was. Wilbur went there for the first time in September 1900. It was a place of windswept, sandy, ‘double-barrelled ISOLATION’, as Tate put it, most of whose fifty-odd households were descended from sailors who’d been shipwrecked there. People fished for a living; children went to school three months a year; the richest inhabitant was said to be ‘Doc’ Cogswell, based on the fact that his brother owed him $15,000. The locals began with the conviction that the Wrights were more than slightly insane, then gradually became persuaded that while that might well be true, it wasn’t the whole story: the brothers were also serious, highly skilled, and above all ‘two of the workingest boys’ anyone had ever seen. Not for the last time, scepticism about the Wrights was dispelled by the impression they created.

Wilbur and Orville spent four seasons on Kitty Hawk, from 1900 to 1903, preferring the late summer and early autumn, before the winter storms. They spent the first three years improving their glider. By this point, Wilbur was in correspondence with other pioneers of flight. They had access to sets of data accumulated by two men in particular, the German gliderist Otto Lilienthal (who’d died in a fatal accident in 1896) and the French-born civil engineer Octave Chanute. But the brothers’ first years on Kitty Hawk taught them something surprising: the data they were using were, in Wilbur’s judgment, ‘worthless’. The elaborate and extensive information they’d been given just didn’t match the realities of flight. Their response was to build a wind tunnel and spend two months testing 38 wing configurations. They perfected their glider in their third summer and then, in 1903, returned to Kitty Hawk with an engine attached to the new machine. They were on the Grand Banks longer and later than usual that year, and on 17 December 1903, with Orville at the controls (they took turns), the Wright brothers’ plane flew for the first time. Man had achieved powered flight.

The rest, as everyone knows, is history, all the way from Kitty Hawk to the £29.99 easyJet offer to Catania you’ve only this minute deleted from your inbox (or maybe that’s just me). Within twenty years, aviation was a thriving business, indeed a whole set of businesses, passenger and freight and military, featuring a whole ecology of practical applications and dazzling feats. This we all know. What is less well known, though, is the freshest and strangest thing McCullough has to tell us. It is that the initial reaction to the Wrights was a non-reaction. A garbled initial newspaper report drew next to no attention. The following summer, the Wrights borrowed a field from a landlord in Dayton and used it to stage a series of experimental and demonstration flights. These were inarguably the first world-historical things ever to have happened in Dayton. The local press, however, didn’t believe in the Wrights, and couldn’t be bothered to go and check. Not a single reporter ever went to look. ‘I guess the truth is that we were just plain dumb,’ one of them reflected years later. The first eyewitness report was written by a bee expert from Ohio called Amos Root, who broke the story in his own publication, Gleanings in Bee Culture. He sent a copy to the editor of Scientific American. The magazine’s response, an entire year later, was to explain why the Wrights couldn’t possibly have done what was claimed of them:

If such sensational and tremendously important experiments are being conducted in a not very remote part of the country, on a subject in which almost everybody feels the most profound interest, is it possible to believe that the enterprising American reporter, who, it is well known, comes down the chimney when the door is locked in his face … would not have ascertained all about them and published … long ago?

So they don’t believe it, because if it were true, somebody would have told them so – leaving aside the fact that somebody already had. It’s a good example of incredulity so unshakeable that it becomes a toxic form of credulity. When the Wrights’ fame spread to France – the first place to take them seriously, and to make the brothers a commercial offer for their invention, subject to a practical demonstration – the cynicism did too. ‘Flyers or Liars’ was the title of an editorial in the Paris Herald. ‘It is difficult to fly,’ the paper sagely noted. ‘It is easy to say, “We have flown.”’

Wilbur Wright – who had gone to France to seal the deal while Orville worked on making the plane at home – was an unusual man. He had a seriousness of purpose and a self-directed, unphoney Ohio groundedness, and he was extraordinarily calm about loudly and repeatedly being called a liar and a fake. The entirely unfounded refusal to believe in his feats had no effect on him. He knew what he and Orville had done, knew that the truth would come out, and simply got on with his work. The effect of this, in turn, was to make people see that Wilbur was not the kind of man to be in the grip of a fantasy or running a scam. Hart Berg, an affable arms dealer who assisted the Wrights in their dealings with the French, spotted this early: Wilbur would be ‘a capital Exhibit A’ in confirming the Wrights’ story, Berg predicted. He was correct. When Wright, on his second visit to France, finally consented to give an interview, he made a profound impression on the journalist:

Mr Hart O. Berg warmed up for the interview by offering me a cup of coffee and laid out a box of cigars. I felt my doubts fly away one by one in the blue smoke. Through curls of smoke I examined Wilbur Wright, his thin, serious face, lit by the strangely gentle, intelligent and radiant eyes … I had to admit: no, this man is not a bluffer.

When on this visit Wright finally finished fixing the plane (which had been thoroughly smashed up by customs officials in Le Havre), testing it and setting up the conditions for a first public demonstration at the racetrack in Le Mans; when he’d done that, and took it for its first spin on 8 August 1908, travelling two miles in two minutes and swerving gracefully to avoid a row of trees, under perfect control, in a full circle, coming back to land feet from where he’d started; when he did that, the crowd in the stands went bananas. ‘C’est l’homme qui a conquis l’air!’ they cried. ‘Il n’est pas bluffeur!’ Ernest Archdeacon of L’Aero-Club de France, one of the most prominent sceptics, had been denouncing Wilbur as an impostor even from the stands at Le Mans. That was before take-off. He now announced: ‘I feel an intense pleasure in counting myself among the first to make amends for the flagrant injustice.’ ‘We are beaten,’ said the aviator Léon Delagrange. ‘We just don’t exist!’

With this, the Wrights really were famous. Wilbur was joined in France by Orville and then by their sister Katherine. They were mobbed, they were lionised. It didn’t bother them. Lord Northcliffe, who became an acquaintance, said that he never knew more unaffected people than Wilbur, Orville and Katherine Wright. The brothers turned their invention into a lively business, the Wright Aviation Co, and their chief vexation in life became lawsuits about patents; they won every one of the nine cases they brought and all three brought against them too. As far as the Wrights were concerned, reputation and pride were the main issue at stake in these lawsuits. And then, just like that, in May 1912, Wilbur died of typhoid. He was 45. He’d had a close call from the disease before, in his twenties, but this time the illness took its course in a few weeks. His father wrote: ‘A short life, full of consequences. An unfailing intellect, imperturbable temper, great self reliance and as great modesty, seeing the right clearly, pursuing it steadily, he lived and died.’

Orville, who narrowly survived the first fatal crash in aviation history on 17 September 1908 – it was his passenger, Lieutenant Thomas Selfridge, who died – kept flying for another six years, before giving up partly because of lingering pains from the crash. He sold the Wright Company in 1915 and devoted himself to research. He was rich, but not obscenely so: at the time of his death in 1948, at the age of 77, his estate was worth the equivalent of $10 million today. He fell out with Katherine when she married; they were reconciled when she was on her deathbed in 1929.

When​ David McCullough’s book came out, it went straight to the top of the US bestseller list, taking up a position right next to Ashlee Vance’s biography of Elon Musk. At which point you may well be asking, who he? The answer is that Musk is the South African-born entrepreneur who runs three of the most interesting companies in America, in the fields of clean energy and interplanetary exploration: SolarCity (solar batteries), Tesla (electric cars), and SpaceX (commercial spaceflight). It’s the third of these companies which is the maddest and most entertaining. Where most corporate mission statements are so numbing they’d be useful as a form of medical anaesthesia, SpaceX’s is ‘creating the technology needed to establish life on Mars’. ‘I would like to die thinking that humanity has a bright future,’ Musk explained to Vance. ‘“If we can solve sustainable energy and be well on our way to becoming a multiplanetary species with a self-sustaining civilisation on another planet – to cope with a worst-case scenario happening and extinguishing human consciousness – then,” and here he paused for a moment, “I think that would be really good.”’

There are a number of suggestive parallels between Musk and the Wrights, beyond the obvious ones to do with an interest in flight. The bishop had very high standards and set no limits on the intellectual curiosity he encouraged in his children; Musk’s father had the same standards and the same insistence on no limits, but was (is) a tortured and difficult presence, ‘good at making life miserable’, in Musk’s words: ‘He can take any situation no matter how good it is and make it bad.’ The Wrights were poorish, the Musks affluentish, but both grew up with an emphasis on learning things first-hand. ‘It is remarkable how many different things you can get to explode,’ Musk says about his childhood experiments. ‘I’m lucky I have all my fingers.’ One very odd thing is a parallel to do with bullies: Musk was set on and beaten half to death by a gang of thugs at his school in Johannesburg; Wilbur Wright was attacked so badly at the age of 18 – beaten with a hockey stick – that he took years to recover from his injuries and missed a college education as a result. His assailant, Oliver Crook Haugh, went on to become a notorious serial killer. Something about these very bright young men set off the bullies’ hatred for difference.

The Wrights took calculated risks. Musk does the same. He seems to have inherited an ‘unusual tolerance for risk’, in Vance’s words, probably from his Canadian maternal grandparents. Joshua Haldeman was a chiropractor who founded a political party in Saskatchewan, married a dance teacher, Wyn, then emigrated to South Africa on a whim. The Haldemans flew single-engine planes from Africa to Norway via Scotland and completed the first single-engine trip from Africa to Australia; they won his ’n hers national shooting championships, tied for first place (competing against professionals) in the Cape Town to Algiers motor rally, and took the family on plane trips to the outback and desert as casually as if they were noodling down the M4 to visit cousins in Bristol. There’s a photo of the five young Haldeman children sitting on deckchairs in the desert reading books with the family’s plane, tent and car in the background – a kind of idyll. Joshua died at the age of 72 when his plane hit a wire between two poles while he was practising landings.

Musk fled his difficult childhood by emigrating to Canada at the age of 17 in 1988. His mother came to visit, and while she was away her daughter Tosca, age 14, sold their house and car; she was in the process of selling the furniture when her mother got home. ‘There is no need to delay,’ Tosca said. ‘We are getting out of here.’ Musk went to university first at Queen’s University in Kingston, Ontario, and then at the University of Pennsylvania, where he did something which gave a clue to his later approach: he took two degrees, in physics and (at the Wharton School of Business) in economics. That dual emphasis was to prove important. In later life, arguing with colleagues over the cost of things, Musk was often to say: ‘Take it down to the physics.’ Armed with his two degrees, Musk went into business with his younger brother, Kimbal. (That’s right: the three Musk siblings are called Elon, Kimbal and Tosca.)

The brothers’ first venture was Zip2, an early internet company that fused business information with maps. Now that we all use Google Maps or variations thereof a zillion times a day, the utility of this idea seems obvious, but it wasn’t in 1995, and the brothers struggled hard, their first office a studio in Palo Alto with a blocked toilet that was ‘literally a shitty place to work’. Musk worked flat-out, at times living in the office, showering at the YMCA, and asking early arrivals at work to give him a kick in his sleeping bag to wake him up so he could get back to work. Zip2 struggled, found a niche selling its technology to newspapers, struggled a bit more, and was on the edge of being overtaken by competitors when, in February 1999, Compaq Computer bought the company for $307 million in cash. Musk and his brother made $22 million and $15 million respectively, and Musk went straight out and sank the money into his next business idea.

In the course of a bank internship in the early 1990s, Musk had come to the conclusion that ‘bankers are rich and dumb.’ He saw an opportunity there, in the form of a crazily ambitious plan to develop what Vance calls ‘a full-service financial institution online’: a new kind of online-only bank. Musk tried to do everything all at once with his new company, X.com, with the ambition of being ‘the online bank to rule them all’. Fintech, as financial technology is now called, has moved on from those pioneer days: most of the many new ideas in it are sector-by-sector attempts to improve how finance works, in acknowledgment of the extent of the regulatory and practical obstacles to new entrants in banking – and also, in part, in acknowledgment of what happened to Musk. His business went through struggles, contortions and a merger before taking defined form as a specialist in one kind of finance, as the online payments company PayPal. Musk became PayPal’s CEO, but a classic boardroom coup ensued, with company executives delivering letters of no confidence to the board as Musk was getting on a plane to go on honeymoon. Musk was forced out, eBay bought PayPal for $1.5 billion, and Musk netted, after taxes, $180 million. Unusually for Musk, a great holder of grudges, he holds none against the people who took over PayPal after him. (One of the sources of disagreement was whether to hold onto PayPal or sell it, with Musk wanting to grow the company. It’s now worth $40 billion, which could be seen as strong vindication of Musk’s position. Whether it would have grown to that size under his leadership is a different question.)

By now we’re in January 2002. Musk’s career up to this point had been both meteoric and typical of the generation of exceptionally bright science and business-minded young men who were quick to latch onto the potential of the internet. He had made a lot of money doing clever digital things. There is a lot of this in Silicon Valley – too much, Musk thinks, for the overall benefit of the species. ‘I think there are probably too many smart people pursuing internet stuff, finance and law. That is part of the reason why we haven’t seen as much innovation.’ One of the early Facebook engineers told Vance that ‘the best minds of my generation are thinking about how to make people click ads. That sucks.’ Because of this generational bias, what Musk did next was very unusual indeed. He took his money and bet it, all of it, on two companies which don’t shuffle electrons around between computers but instead try fundamentally to alter the direction of real-world things: Tesla and SpaceX.

There is a spectrum of opinion of Musk’s activities in these areas, and of Musk more generally, ranging between two extremes. At one end are those who see Musk as a blowhard and a braggart, a bullying self-promoter and bullshit artist: this was a popular view in late 2008, when both Musk’s companies were in what looked like terminal difficulties. In Tesla’s case, the company was trying to do something generally known to be impossible. Tesla was trying to be a new car company. The last successful startup in the American automobile business was Chrysler, founded in 1925. In the car industry, all the knowhow and workforce and supply chains are in Detroit. Musk was trying to set up his firm in California, using lithium ion batteries to make an all-electric car which people would want to buy not because it was more ethical than any vehicle powered by an internal combustion engine, but because it was better: faster, safer, roomier, more fun to drive. The idea was to keep costs down by manufacturing as many of the parts in-house as possible, against the industry norm of buying in parts from outside manufacturers. The dream: faster, better, cheaper. The reality: spiralling costs, endless manufacturing problems, and the only thing travelling with any velocity the deadlines as they zoomed past. By May 2008, the snarky car blog The Truth about Cars had started a ‘Tesla Death Watch’. The company had taken 1200 deposits for its new car, the Roadster, but had delivered fewer than fifty vehicles. It was joining the long line of would-be disrupters and would-be innovators who had tried and failed to take on the sluggish behemoths of Detroit.

At SpaceX, things were worse. The company had the same approach as Tesla, attempting to keep costs down by manufacturing in-house, since Musk’s crucial insight was that cost is central to his long-term goal. ‘The thing that’s important is to reach an economic threshold around the cost per person for a trip to Mars. If it costs $1 billion per person, there will be no Mars colony. At around $1 million or $500,000 per person, I think it’s highly likely that there will be a self-sustaining Martian colony.’ So price matters: and what that meant was building everything in-house, testing everything in-house, arguing with suppliers to force costs down, testing and repeating – ‘iterating’, as they say in the software business. But space rockets are not software, and it was unclear to some observers whether this fast-and-cheap, suck-it-and-see, build-and-iterate approach would work when it came to building rockets. Space is big business, worth around $200 billion a year, but while most of the satellites launched into orbit are corporately owned, the business of getting them up there is the prerogative of governments: only they have the patience and capital and accumulated knowledge to do it. Most of the time, capitalists with a business plan involving satellites turn to the Russians to get them into space. Musk had other ideas.

The testing ground for his vision was Kwajalein, one of the Marshall Islands. SpaceX’s rocket was called Falcon 1. A team of engineers lived on Kwaj (as it’s known) for months, working under hard conditions as they tried to become the first private company to build a rocket capable of travelling into orbit and back. The first rocket went up on 24 March 2006, and 25 seconds later went straight back down, the debris landing 250 feet away in a coral reef and the payload coming (conveniently!) through the roof of the workshop. The second rocket went up on 15 March 2007 and this time didn’t come back down, but only because, five minutes into the flight and on the very frontier of space, it exploded. The third rocket was launched on 2 August 2008 and while it didn’t explode per se, it did crash, because the first and second stages failed to separate. The rocket was carrying a payload of experiments for the US Air Force and Nasa (a nano-sail, an experiment concerning yeast), and cremated human ashes for a space burial.

In public Musk was bullish after the third crash. In private, he was desperate. SpaceX was burning through $100,000 a day, and if the fourth launch didn’t succeed, there wasn’t going to be a fifth, because the company was going broke. He didn’t have enough money to keep both his companies in business. ‘If I split the money, maybe both of them would die. If I gave the money to just one company, the probability of it surviving was greater, but then it would mean certain death for the other company. I debated that over and over.’ As Musk was brooding on that, in the last days of 2008, the economy was getting steadily worse.

At that point​ , most interested observers thought Musk was toast, and the sceptics felt they’d been proved right. There has always been another school of Muskologists, though. This camp sees him as a visionary genius: an impossibly demanding boss, yes, but one who regularly achieves the impossible as a result, and the man most likely to solve our addiction to carbon, save the planet from global warming, and set us on course for our interplanetary destiny, in the meantime making a very great deal of money for himself and his shareholders. This was a popular view around the end of 2014, when Vance was finishing his entertaining book, and is a big part of the reason it shot to the top of the bestseller list. Musk did not go broke in 2008: the fourth Falcon 1 launched successfully in September (though with only a dummy payload: nobody now trusted it enough to risk real cargo). On 23 December, SpaceX landed a Nasa contract to supply the International Space Station, worth $1.6 billion. That saved the company.

Today, SpaceX is launching a rocket into orbit roughly once a month; has a contract to put astronauts into space for Nasa; has one big rocket in service, Falcon 9, which has made 18 successful launches, and is developing the biggest rocket in the world, the Falcon Heavy; has three different families of rocket engines, Merlin and Kestrel and Draco, with two more under development; and is working on an immensely groovy spacecraft for human use, the Dragon V2. Musk is pursuing the idea of making his rockets reusable by coming back down to earth and landing, which many engineers think is impossible. To keep things interesting, the rockets still sometimes blow up: on 28 June, a Falcon 9 that was meant to visit the ISS and make a controlled return exploded two minutes after launch. But the company has respectable backers, with Google and Fidelity between them buying 8 per cent of it in January, at an implied valuation of $12 billion. Making money, however, is not the point of SpaceX. ‘The point is to maximise the probable lifespan of humanity,’ says Musk. ‘I would like to die on Mars,’ he adds. ‘Just not on impact. Ideally I’d like to go for a visit, come back for a while, and then go there when I’m like seventy or something and just stay there.’ To put this ambition in context, Musk at the time of writing is 44.

To save SpaceX, Musk did not have to sacrifice Tesla. If the survival of his space company was a triumph of engineering, the survival of his car company was a triumph of the bluff. Musk scraped together $20 million to lend to Tesla so it could pay its bills, and talked his investors into matching the amount. Vance theorises that some of those investors wanted the firm to go broke, so that Musk could be sacked as boss, then the company recapitalised and sold off to one of the big auto manufacturers for the sake of its intellectual property – a perfectly sensible plan, if not an especially admirable one. Instead Musk got his money on Christmas Eve 2008, the day after the Nasa deal for SpaceX, when Tesla was within hours of bankruptcy.

Today, Tesla is worth $34 billion, and its shareholders include some of the world’s main car companies, prominent among them Mercedes Benz, the people who invented the internal combustion engine. Their investment in Tesla was one of the first real signs that the company’s technology lived up to the hype. The thing about electric cars is that they have the potential to be wonderful. The internal combustion engine is a machine that creates a precise mixture of air and petrol, carefully ignites it, then uses the ongoing controlled explosion to generate mechanical revolutions, which it transmits from the engine through gears to a vehicle’s wheels. By contrast, an electric motor just whizzes along and can transmit revolutions directly anywhere it wants: no mix, no explosions, no gears. The result is smaller, lighter, safer, more efficient: in short, better – at least in theory. The problem has been the battery. Fossil fuels deliver energy as and when needed. Other kinds of energy have to be stored in a battery, and batteries, as we all know, basically suck. They are expensive and unreliable and tend to run out of power. Put your foot down in a petrol car, and it goes. Put your foot down in an electric car and it takes you to the end of the road and then conks out. This is known as ‘range anxiety’, and has been the main obstacle to the adoption of electric cars for about a decade.

The central insight at Tesla was that this need no longer be true. Lithium ion batteries, the kind which power most computers and phones and high-end gadgets, have over time got much better – much better than most of us realise, because as they get better, engineers add more and more features to our devices, which therefore consume more and more power, so that the batteries seem to be standing still. Battery life stays the same, from the consumer’s point of view, even as it improves. What the Tesla crew spotted, though, was that lithium ion batteries are now so good that if you pack a car with them, and the car is nice and light – which a car made of the latest materials, without an internal combustion engine, is able to be – that car can a) keep going for much longer than any existing electric car, and b) accelerate like the proverbial bat out of hell. If you then c) make the car look really nice and modern and desirable, you’re going to have a serious hit on your hands. The car that did all these things was the Tesla Model S, launched in 2012 and currently retailing for $80,000, or £55,000. The car looks gorgeous, travels 350 miles on one charge, seats seven adults, accelerates from 0 to 60 mph in 2.8 seconds, stores lots of stuff because it has both a boot and a front trunk or ‘frunk’, and can be recharged for free and without any carbon emissions at a network of solar power charging stations. This means that, as Musk points out, ‘even if there is some zombie apocalypse, you’ll still be able to travel throughout the country using the Tesla Supercharger system.’ The electric motor that makes all this possible is the size of a watermelon.

Musk’s investment in batteries has, as a spin-off, led to his role in a company founded by his cousins the Rive brothers (descendants of the same risk-loving Haldeman grandparents). SolarCity is a solar energy company, the largest installer of solar panels in the US, which uses the same batteries Tesla manufactures for its cars. Batteries are a crucial component of renewable energy, since they enable the consumer or business to store energy and use it when needed. Musk has set up the biggest lithium ion battery factory in the world, which makes a very good fit with SolarCity – no surprise, since the company was his idea in the first place, and he’s its chairman. Vance points out that ‘enough solar energy hits the earth’s surface in about an hour to equal a year’s worth of worldwide energy consumption from all sources put together.’ That fact is well known, but hardly anybody has been able to make a viable business out of the insight: SolarCity, with a market cap of $5.6 billion, is one of the exceptions.

A bestseller list is not a Rorschach test, but it can tell us something about the subjects currently on a national mind. The juxtaposition of the Wrights’ story with Musk’s suggests that America is thinking about innovation and new technologies, and perhaps that it deeply wants to believe in the new thing, to believe that the new inventions will be as consequential as the old ones proved to be. That’s the crux. The management consultancy firm McKinsey trains its acolytes to reach a climactic moment of explanations with the phrase: ‘And the “So what?” is …’ So, what is the ‘So what?’ of Elon Musk? That depends, as it always has done, on which camp you’re in, Muskophile or Muskophobe.

The probable answer is that both are right: Musk is indeed a big-talking bully and boaster, an over-promiser, but he is also something very close to a genius, not so much in physics or in business but in the fusion of the two. Nobody creates the two most successful clean-energy companies and first commercially viable private space company by chance. However, Musk’s innovations could all come to pass, with SpaceX heading for Mars by the end of the next decade, and electric cars increasingly popular in the first world, and solar energy increasingly practical, and yet how different would the world really be for most of its seven billion inhabitants? His businesses employ 15,000 people, which is quite a few, but on the other hand is also less than half as many as work in a single Hyundai factory in South Korea. Also, the sheer scale of the capital and resources deployed in Musk’s businesses shows just how hard it is to innovate fundamentally in these industries. Two tinkerers changed the world with an invention they knocked up in their spare time in a workshop. Musk deploys tens of billion dollars in capital and a huge amount of brainpower and gives a lot of pleasure and entertainment in the process, but the upshot is still disputable.

Don’t get me wrong: I love the idea of SpaceX. I follow it on Twitter, I watch its launches when the time-zone difference permits. I would love to own a Model S. I think that by 2050, or whenever it is that the world has successfully transitioned away from fossil fuels, Musk will be seen as a hero – and so will everyone else who helped to make electric cars, and solar energy, a daily reality. Lots of people have seen the value of these things, but Musk has been able to make them into viable businesses, just as lots of people saw the potential of powered flight but it took the Wrights to make it happen. As for human spaceflight, I think it’s an inherently progressive activity, not so much in its practical consequences but in the way it changes our species’s frame of reference. The modern ecology movement was in effect created by the image of the whole earth, vulnerable and isolated and full of life, sent back by Apollo 8. The progressive atmosphere of the 1960s was profoundly influenced by the space project, by the idea that we as a species can Do Better. The prospect of humans on Mars would have a similar effect. At least that’s what I think – but I’m aware this is a minority view. In any case, perhaps the fact that you have to ask the question at all goes some way to answering it. Nobody ever needed to ask the ‘So what?’ of the Wright brothers.