The human race is doomed. Not today, almost certainly, and probably not in the next week or so. But, sooner rather than later, the curtain will fall on the last act of this crazy, beautiful, tragic, wonderful carnival we call life on Earth, at which point we (or, at any rate, our descendants) will all wish we had listened rather more carefully to Elon Musk, the 21st century’s prophet of doom.

That, at least, is the apocalyptic vision of humankind’s future according to Elon Musk.

The founder of PayPal is a ­real-life Tony Stark, of Marvel fame, applying his billions and his feverish imagination not to the creation of flying Iron Man suits but to a series of seemingly more pragmatic projects, each in its own way designed to save life on Earth.

Except, according to Mr Musk, life on Earth cannot be saved. Electric cars, solar power, hyper-loops – all these ventures, designed ostensibly to resist the strangulation of the planet by global warming, are mere stopgaps, placeholders for his ultimate ambition.

Mr Musk’s SpaceX rocket programme, which has already seen his engineers develop reusable rockets and successfully servicing a Nasa contract to resupply the International Space Station, is just part of it, a series of technological stepping stones towards the greatest prize of all: Mr Musk’s place in history as the man who colonised Mars and saved the human race.

Mr Musk outlined his plans to colonise the red planet at the International Astronautical Congress in Guadalajara, Mexico, in September. Of course, he’s not the only one gazing up at the fourth planet from the Sun. Nasa, for its own, federal funding-related reasons, has similar ambitions and, depressingly, a Dutch company is seeking volunteers for a one-way trip to take part in a life-on-Mars reality TV programme. But Mr Musk is the only one confidently predicting he’ll be turning Mars into a home away from home by as soon as the mid-2020s.

Why? “History,” he told the audience in Guadalajara, “suggests there will be some doomsday event, and I would hope you would agree that becoming a ­multi-planetary species would be the right way to go.”

It was a jaw-dropping statement, but one that has been greeted with near-universal enthusiasm.

In 2005 Louis Friedman, co-founder with astronomer Carl Sagan of The Planetary Society, wrote of the “survival imperative of becoming a multi-planet species”. We could not, he insisted in the book Human Spaceflight: From Mars to the Stars, “put all our eggs in our earthly basket. It has too many forces that might cause it to fray – forces such as asteroid impact, large-scale conflict and war, pandemics, global climate change, and other types of environmental destruction, such as resource depletion and scarcity”.

Now Mr Musk is in danger of making Mr Friedman’s dream a reality. So much for former American president Barack Obama’s climate-change rallying cry, “We only get one planet. There is no Plan B.”

All that remains, it seems, is to overcome the technological barriers. How to go about that was one of the talking points at the recent Aspen Abu Dhabi Ideas Forum, at which big names from the fields of astronautics and commercial space exploration gathered to address the question: “Can the human race live sustainably beyond Earth?”

The short answer? Sure we can. But perhaps the most important question to be asked at this stage is not “how?” but “why?”.

In his 2008 book Dark Side of the Moon, Gerard DeGroot, professor of history at the University of St Andrews, Scotland, made a convincing case that the entire Apollo lunar programme had been nothing more or less than a vainglorious exercise in “magnificent madness”, set in train by president John F Kennedy for purely political reasons. Landing on the Moon, the American people were told, “would bring enormous benefit to all mankind”. In fact, it was “an immensely expensive distraction of little scientific or cultural worth. The American people … were persuaded to spend $35 billion on an ego trip … and then were told that a short step on the desolate lunar landscape was a ­giant leap for mankind.”

Fast-forward 47 years and explorer-evangelism is in the air again. Profr DeGroot’s view today is that the idea of colonising Mars as a “lifeboat” for life on Earth “falls apart the minute one applies any practical or philosophical logic”. For a start, “why go to Mars? We know it’s a barren rock which makes Antarctica look like a tropical paradise”.

We know an awful lot about Mars – we have, after all, been sending hardware there since the early 1960s – and what we’ve learnt, and continue to learn, helps us to refine our understanding of the universe and our place in it. One of the key things we have found out is that, with an atmosphere comprising 96 per cent carbon dioxide, ferocious dust storms and an average temperature of -60° Celsius (but -125° on a bad day), Mars is seriously inhospitable.

We’ll know even more about Mars after 2021, when the UAE Space Agency plans to mark the 50th anniversary of the founding of the nation by putting an unmanned spacecraft in orbit around the planet. Its mission will be to harvest invaluable information about the planet’s weather systems that will boost our knowledge of meteorology here on Earth.

But sending orbiters, robotic surface vehicles and even building an outpost to explore Mars is one thing. Going to live there for good is an altogether different proposition, and one laden with all kinds of philosophical and moral baggage.

Mr Musk, blessed with the supreme confidence of which all billionaires are possessed, talks enthusiastically about “terraforming” Mars, to create an earthlike atmosphere. What he has in mind, as he explained to an incredulous Stephen Colbert on The Late Show in September, is warming up the planet by exploding thermonuclear weapons over its poles.

Pause there for a moment to consider that global warming and thermonuclear war are two of the looming threats inspiring Musk’s call to abandon Earth for Mars. Billionaires with grandiose plans seldom have time for irony.

But the crucial point, as Prof De Groot says, is “if we can terraform Mars, then surely fixing whatever is wrong with Earth will be a tiny challenge in comparison?”

It would, surely, be more logical – and incalculably cheaper – to plough all the effort and money that would be necessary to move our home to Mars into solving the problems we have created here on Earth. Poverty, hunger, disease, global warming, overpopulation, the ever-looming threat of nuclear war … yes, each of these represents a titanic challenge. But, as president Kennedy himself once noted, all our problems are “man-made [and] therefore they may be solved by man”.

Committing to Mr Musk’s “head for the hills” plan, running away from instead of dealing with our problems here on Earth, would have dangerous consequences. For example, what would become of the considerable effort that is being put into reducing our dependence on fossil fuels and combating global warming? After all, if we’re planning to vacate the planet, why bother?

But there’s a more fundamental issue at stake, says Prof DeGroot: “If man cannot exist on the bountiful planet he has been given, surely that is justification enough for his extinction?”

The idea that the human race should be preserved by colonising another planet is, he says, founded on the egotistical belief that humans are special. But the fact that man would have failed on this planet “would surely demonstrate that man is not special at all”.

We are a clever species, of that there can be no doubt. But we, and Elon Musk, may yet prove to be too smart for our own good.

Jonathan Gornall is a frequent contributor to The National