5 Reasons Going To Mars is a

I rather think you are misunderstanding my last point. What I'm saying is that over population and climate change and millions of refugees - which are adding to the over population problems - will help persuade politicians of space nations to approve of such things as high frontier habitats and the politicians will deem that their approval is needed whether it should be or not. You are right of course that what is really needed to persuade the investors will be a good chance of good profit. Asteroid resources and powersats may help but someone will have to profit from one or other before either can really take off.