I think of Spacex being more like the rail roads in the 1800's. Elon is building the infrastructure so that when launch costs do come down, there will be an explosion of off Earth economic activity. And Spacex will be there with the tickets.<p>Colonizing Mars may be a driver and talking point now, but will be minor in the long run. Asteroid mining, orbital habitats, Moon resorts (with flying domes ala Heinlein), Comet water chasing, it's all open. Mars' role may be huge, it's sooo much easier to get to orbit from Mars than it is from Earth.