Let's get lab grown meat going so we can free up all that cattle land in the middle of the country, build some well planned cities with high speed rail connecting them and spread out a bit.
Land is not, and will not for the forseeable future be the point of contention in the US, it's the rail connections and building 'well planned cities' that people actually want to live in that are basically impossible.
How would building a modern city in an open plain be harder than retrofitting a century (or more) old city, wrt transit, zoning, ecological concerns, etc?
I'm not saying it's trivial to build a city. I'm saying a modern city does not jeed to work around the many many layers of complexity and existing city brings