> The only bizarre thing is that after having people on the moon fifty years ago, nobody bothered to go back. The natural progression
Natural progression? :)
Contemporaneous with the dream of "we will settle space", was one of "we will settle the continental shelves". The progression? Skylab-like habitats, abandoned, nothing ISS-like, and now only temporary work camps. A tourism of many brief shallow visits, and a few shallow subs and hotels. Military subs. No large commercial subs, a few semi-submersibles. Limited shallow seabed mining. Very limited floating towns. Drift nets and bottom trawling. No bases and cities under the sea. No commercial divers looking around at the seafloor and thinking, "I want to raise my family here someday". Lessons? Find some space resource extraction, for which robots are inadequate, and with better economics than seabed mining. Militarize space. Encourage recreational high-altitude ballooning, parachuting, and suborbital.
"We will settle the Antarctic"? Science bases grew a bit, got prettier. Little commerce, no industry, no extraction, no settlement. Some tourism, visiting ships, and tear-down-each-season hotels. Emphasis on preservation. So a planetary protection "Mars international-park planet: take only photographs, leave only footprints"?
"We will colonize the air"? Societal emphasis on safety cripples innovation? Clear-eyed investors deny funding? (Early railroads and canals often operated profitably... after a bankruptcy or three disposed of the cost of making them.) No floating cities. Few aerostats. Enormous ratio of paper dreams to metal. Lessons... ?
"We will settle the deserts"? Cairo's cities in the sand? Diversely poor, industrial, and gated. China's ghost cities? So focus on incentivizing developers, and then move something there to attract people?
So many natural progressions to choose from. :)