So, send them to Coventry, set up a ghetto or Bantustan, or be glad there are a lot of islands as in Brave New World.

I misread your "else" in "you get a one way ticket somewhere else" as outside of the US, not partitioning the US.

Historically this means the US will still be spending a lot of money on these so-called freeloaders, not only for internal border control (people, smuggling) but also pollution emissions, water flow, and all the other boring crap usually handled by national law and interstate compacts.