A lot of people don't seem to get what he's on about, but the entire history of humans is one of moving around, exploring and settling new places. It would actually be very weird and novel to <i>not</i> settle Mars. The last major settlement was the Americas after Columbus, and that will likely be what happens here, minus the genocide. Things do improve a bit over the years.<p>The next question is, why Mars in particular? And the simple answer is, it's the closest thing to Earth in the Solar system. The moon is close by, but it's harsh, desolate and resource-poor. Weak gravity, terrible 'days', no atmosphere etc. Proximity is the only thing it has going for it. Mars, on the other hand, is more like the most extreme places on earth - a combination of Antarctica and Atacama - very hard but doable. Once you have regular, not-super-expensive transport, proximity is not such a problem.<p>The next question is, how would you get there? And this is where all the fun technical talk is happening. You'll need Big Freaking Rockets to escape the Earth's gravity, but then there's a lot of ways it can go after that, for example, can they make a self-fueling MAV in time for 2024? Or it is easier, though more expensive, to just shoot more BFRs then?<p>Then the question is where will the money for all this come from? Well, I don't imagine SpaceX will be doing this alone. Space agencies spend a bit of money on this, SpaceX makes a profit from their launch business and Musk has said SpaceX will go public in order to fund their Mars colony. Several hundred billion is a lot of money, but spread out over decades and amongst space agencies and companies is doable.<p>The final question, and one Musk hasn't answered very well IMO is why would millions of people go to Mars? What are the economics of it? Getting a couple of hundred (or thousand) pioneers is not a problem, you'll find tons of people willing to risk everything for far less, but how would you get million person cities up there? The best answer I have is, people will go there because it will be the only place where new things are possible. I think we're starting to see a backlash against "disruption" and it's somewhat justified. Living peacefully with 10 billion humans on one place is hard enough without some of those people rocking the boat. I'm talking about things like AI, human genetic modification, but also just plain old politics, traditions, power structures, etc. Mars would be new wide-open place where you can set up shop and do anything, whether founding new societies or doing dangerous engineering. This would also work very well economically, as Earth would be able to outsource a lot of experimentation and risky activities and there would be a profitable information (not resource) based planetary trade.