>>12765584Let's be honest here. Above ground structures are a luxury thing until we've our needs filled.
Needs & wants. Our government wants above ground structures for a glorified flag planting mission.
Underground structures means that you don't need to ship in build materials other than tunnel reinforcement stuff.
Once you have a tunnel individuals & pairs would pay for an apartment to be build into the side of a tunnel.
That instantly jump starts an economy as people would pay for an apartment to be built 2 years ahead of them going to Mars.
That's just living spaces. With underground structures you quarry out stone to build liquid holding tanks for sewage treatment and storage of millions of gallons of water, which means long hot showers.
it also means we can pump methane & other chemicals into the ground like the strategic oil reserve.
Industrial equipment gets to stay out of the elements, and you could build underground rocket test stands in sealed off halls.