Do you really think that adopting a sustainable way of life is unfeasible, while establishing a self-sustaining colony on another planet is? Many of the changes I am talking about are already taking place. For example, renewables have recently become a viable alternative (http://www.sciencealert.com/india-says-the-cost-of-solar-pow...) and population growth is projected to taper off after 2050 (http://abcnews.go.com/Technology/story?id=98371). The only thing that can hold these solutions back is strong opposition from the beneficiaries of the current system. They will fight back, but I think that the odds are stacked against them.