Once we have recycling food replicators we can live anywhere. No power grid, no government services, no civilization outside our little house. Put everything in an airtight box and you can live in a self contained habitat in the asteroid belt. The food replicator that recycles our waste is the ONLY missing piece.
If a job has so little value that only illegal workers from Mexico can do it, then that job has already been exported to Mexico. Except that American taxpayers are covering the bills (police, school for kids etc). America would be better off just making it official and let Mexico have those jobs directly (no more subsidies etc).
The magnetic power field is easily filtered, so radio repeaters would still work. The thickness of the aluminum is not really important, they make capacitors out of aluminum foil and this metal room is just a big capacitor. Don't use thumb tacks, you'll get zapped. Strong magnetic fields are known to affect human cells.
1-The outer space treaty prohibits doing that, and they don't have the military to enforce such a claim. 2-If China goes broke trying to colonize the moon it means they don't go broke starting WW3, not a bad outcome.