[Shryke]

But which one has the resources to make it worthwhile?

Can you please cite evidence to suggest Mars' crust would not contain rare elements?

My ultimate point was that Mars will most probably be the second self-sustaining human planet, mostly becuase it is easiest to colonize. Can you argue otherwise?

[RightWhale]

I wrote off Mars decades ago. It wouldn't be useful as a base for asteroid mining. It could support a fair number of monasteries and science outposts, maybe a Plymouth Bay Colony now and then. But look at Venus! It could be cleaned up, spiffed up, and marketed as the New World, the thing America was supposed to be except this time for real. Venus is our twin, you know.

[PatrickHenry]

My ultimate point was that Mars will most probably be the second self-sustaining human planet, mostly becuase it is easiest to colonize. Can you argue otherwise?

I'm not keen on terraforming. I suspect it would be a whole lot easier, and cheaper, to transform the Saraha desert. For getting work done in space, off-planet habitats seem like a more practical solution. That is, until we can get to other planetary systems where we might find more congenial planets.

[ChicagoHebrew]

My ultimate point was that Mars will most probably be the second self-sustaining human planet, mostly becuase it is easiest to colonize. Can you argue otherwise?

Yes. Europa.