That's true, as long as there's something else surrounding the city that is happy to take those people of the city's hands. If there isn't, you can really only

That's true, as long as there's something else surrounding the city that is happy to take those people of the city's hands. If there isn't, you can really only banish them by driving them outside the 200 mile zone and abandoning them there. The "humane" part kind of falls away in that case.