Mr Red,

"It is all about profit. However that is measured. "

As was the exploration and colonization of the Americas, and all the European Empires expansions.




"I personally think mining asteroids has a better chance of pay-off, once we figure how to keep a lander glued to an irregular surface in virtually zero G."

Agreed, in the short term. A new source of resources, not in a gravity well.
Attachment is fairly easy- Magnetic to metallic asteroids, sunken in anchors ( by melting) to the ice and rocky ones.




"I don't yet see what technology will come out of sending men or menesses to Mars will contribute to solving the privations of Global Warming."

Closed loop resource recycling, non-carbon energy production, CO2 utilization for hydroponics... and all the ones we can't see until they are developed.



No need to terra-form Earth- we already have an atmosphere and lots of free water!

But remember, the difference between a self-contained space colony and a star-ship is only propulsion.