People should be free to come and go and work and play anywhere they want, anywhere on the planet.
So, for example in a neighborhood, everyone is free to live in whichever house they please, with no obligations for maintenance or utilities (i.e. the duties and responsibilities of citizenship). How would that work out?
First, naturally, people would head to the nicest house on the block. Eventually, it would get too full and too dilapidated so people would move to the next nicest house, and so on until the "niceness" of each house reaches an equilibrium point where there is no longer incentive to move because the next house is just as nice (or not) as the one you're living in.
Should anyone try to "fix up" a house and succeed, theirs will become the nicest house on the block, attracting everyone to move in. Very quickly, their effort will be negated and everyone will move back out since it isn't nice anymore.
The only stable equilibrium for this system is one in which all houses are equally miserable, and getting even worse. That's why houses have locks, and that's why countries have borders.
For much (most?) of our history federal income came exclusively from tariffs, and the President is very fond of evoking that era. It would not be unprecedented for it to happen again.
Can't argue with the moderation given the slant of this community (I landed here from "All"), but I continue to maintain I've been posting in good faith.
Have a blessed day.