Because it is informative about his true intentions when he talks about going to Mars. He is not stupid enough to think that we currently have the capability of

Because it is informative about his true intentions when he talks about going to Mars. He is not stupid enough to think that we currently have the capability of building a Mars colony that would be even remotely close to sustainable in the face of a global disaster on Earth. Rather, it's quite obvious he's a modern day Ross Perot who has perfected billowing up his companies on the taxpayer dime. And a manned trip to Mars represents the fattest international contract the world has ever seen. If he bamboozles the world into financing this interplanetary field trip, he's going to personally end up with a net worth in the trillions...