Will Geoengineering Kill Us or Save Us?

1. Send a factory factory to a carbonaceous chondrite asteroid

2. Factory Factory builds a factory that builds a solar sail factory

3. Solar sails maneuver on their own power to the Earth-Sun L1 point

I can picture much of the chemical factory involved, it looks something like

https://www.netl.doe.gov/research/Coal/energy-systems/gasifi...

but also something like a conventional petrochemical factory and it probably uses solar concentrators for something. Thin film construction seems possible. There are a lot of problems that are like trying to build a ship in a bottle except you're in the bottle and trying to build a ship outside the bottle.

What has me scratching my head is:

a. Do you have to send humans? If the factory can be started up and run autonomously it saves the need to build a human habitat.

b. What do you do with the volatiles? I think when you punch through the crust of an asteroid you might get a dangerous quantity of gas, which is also highly valuable. You might have to devolatize the asteroid before the metal line and storage tank factory are online.

Why covering empty fields with mirrors is not discussed? It's all been calculated, it's costly but will work.