"At <a href=""https://www.youtube.com/watch?v=50r-5ULcWgY&amp;t=51m40s"">51:40</a>", I'm compelled to argue that it is easier to do both, if we incorporate or integrate both's solutions by learning how to do both, simultaneously.<br>Thus, terminating the knowledge gained by learning how to colonize Mars at the vast scales of the dreams of Elon, simply based upon <b>valid</b> priority, will most probably result in limiting our knowledge about global warming prevention.<br>You may argue that the two have nothing in common, that taking priorities is the better strategy.<br>However, to finalize my argument, we wouldn't be the space based race even capable of building the vast and <b>interactive</b> shadow casters needed to <b>actually</b> prevent the global hell heating to come. The only better argument is the use of the Moon instead of Mars, to learn how to become that kind of <b>INDUSTRIAL</b> - and swiftly (then we could easily colonize Mars too).