Futurists often dream about the colonization of Mars. I put myself in this category of people. Of course, Mars colonization would be an extremely expensive project. Many would rightly argue that money is better spent elsewhere, especially if the funding for Mars colonization would be paid for by taxation. Why should the people be forced, at gunpoint, to pay for the pet project of sci-fi enthusiasts?
Mars colonization advocates argue that Mars should serve as a back-up planet in case anything happened to Earth. I don't buy this argument. What might happen to Earth that wouldn't happen on Mars? Nuclear war? You think Mars can't be nuked? Climate change? You think the climate on Earth could one day become worse than the climate on Mars? Asteroids? You think Mars has better protections against the hazards of space than does Earth, despite the fact that Mars has no atmosphere to burn up space-rocks and no magnetic shielding to protect us from radiation?
One of weaker arguments for Mars colonization is that it might have resources we can exploit. Even if that were true, it does not make economic sense to exploit these resources until we have technology that dramatically lowers the cost of accessing space. Mars colonization advocates who insist that we push ahead to colonize Mars with existing technology cannot justify the enormous cost on economic grounds.
A more clever argument for Mars colonization is that it would inspire people to pursue a career in science and technology. It would bring about a culture of innovation that would propel our civilization into a glorious future. Neil Degrasse Tyson makes this argument. I think it's backwards. You cannot get Mars colonization without an existing culture of innovation. In the absence of an innovative culture, how would you pull off a stunt like landing on the Moon? Obviously the innovation has to come first. Landing on the Moon is a side effect of having an innovative culture.
In my opinion, colonizing Mars in itself is not important. What is important is building an innovative, freedom-loving, entrepreneurial culture. The side effect of having such a culture is Mars colonization. Innovation will lead to technology that will dramatically lower the cost to access space. Simultaneously, innovation will lead to an increase in wealth. If enough people can afford to access space, they will do it. They will explore. They will seek out glory by doing what no has ever done before. This is in our nature.
So how would freedom and entrepreneurship lead to cheaper access to space? Right now, simply getting off the Earth is the most expensive part of getting to space. Rockets are not fully and rapidly reusable. It is like throwing away an entire Boeing 747 after using it just once. Any company that develops a fully and rapidly reusable rocket will completely and totally dominate the space-launch market for commercial satellites. Therefore, there is a huge market incentive to develop this technology. A freedom-loving, innovative culture will easily produce a company that will rise to the challenge to meet this market-demand. A culture that stifles freedom and entrepreneurship cannot and will not be able to rise to the challenge.
If you are somebody who dreams of the colonization of Mars, and I am one of these people, getting the government to force others to pay for our fantasy is not the way forward. It might work in the short-run. The Moon landing was exciting and all, but what has come of it? The Atlas-V was the most powerful rocket man has ever created, and we've been going downhill ever since. Today, America doesn't even have the capability to put a man into low earth orbit, let alone land a man on Mars. So having the government pay to explore space is short-sighted. As soon as the government runs out of money, it will cut off funding because government programs do not pay for themselves.
Harnessing the power of the free market is a more relaible and sustainable way to drive the development of space technologies. The commercial space launch market is a huge market that provides a powerful incentive to develop better rocket technologies. Mining asteroids for rare-earth minerals (that are not so rare in space) is another potential market force that can drive the development of space technologies. We don't need the government.