[ 21/2/20 – meeting 25 Feb 6-9pm SF time]
It is challenging.
To my understanding, everything changes once we have systems capable of fully automated remote mining and manufacturing (should have those within 15 years, if such developments are given appropriate levels of support).
Once we can create such a system here on earth, then we can send one to the moon, and if it takes a full lunar month to create a copy of itself, then in less than 3 years the population of production units will cover the surface of the moon in solar cells, and then serious engineering becomes possible.
Lunar mass can then be accelerated to orbital velocities by large ground based linear motors on the far side of the moon without needing chemical propulsion.
With significant amounts of mass in orbit (10^9 km3 – 10^18 m3), we can start constructing serious numbers of large orbital habitats (large rotating cylinders inside a non-rotating radiation and impactor shield made of less refined rock) capable of holding hundreds of thousands of people with lots of space and technology and freedom.
The idea of money really loses meaning once we have fully automated production. We need alternative value and planning metrics than those measured in markets.
And we need tech like that to allow us to build a large set of existential risk mitigation technologies. One example being a very large set of very large telescopes, to give us enough warning to be able to deflect anything heading our way that might pose a risk to the earth or to any of the orbital habitats. Another set of systems at L1 to allow us to modify solar radiation received by the earth to maintain sea level and climate with acceptable tolerances (no more ice ages or climate change concerns). Etc.
If we are to allow for freedom and exploration of real novelty, then some of those realms may need to be explored in places that do not pose unacceptable risk to others. Orbital habitats are a good place to start. Having a hard vacuum around experimental biotech is probably a very good idea. Some things might be deemed so risky that a habitat might be required to be sent to the other side of the sun, to provide sufficient security to those on earth should something go seriously wrong with some classes of experiment.
For the sake of humanity as a whole, and for freedom as an idea taken both seriously and responsibly, these are issues that need to be addressed. The moon is the only serious source of matter easily able to be placed in earth orbit.
Another large rock hitting the earth is not a matter of if, just a matter of when, unless we have very large scale technology like this in place. We need our thinking to be enabling of such security, not condemning ourselves to extinction for a failure of imagination.
Lots of other earth based problems become easy to solve when technology at this scale is nearby and available.