but the only reason we will stay is because there is some economic advantage to be gained. The evidence of this is right under our nose. As far as we know now, there are probably resources in Antartica more accessible than any on Mars, but no one is planning to develop them right on our own planet.

I suppose if we had early warning of some massive extinction event there might be some effort to colonize Mars as a last resort, but even that might not motivate us sufficiently.

I hate to say it, but space advocates will never get us there to stay. It will have to be profit driven or economic neccessity. There has to be some pay off for Earth.

Of course all this could change if space access becomes so cheap a new generation of explorers and adventurers are born, or if one of our rovers stumbles on a mountain of gold or other coveted resource. The former will happen at some point I suppose. The latter is a pipe dream I suspect.