I think what's happened in New York and California shows that you need some degree of immigration enforcement to prevent people who don't understand how free democracies work from overrunning and destroying them.
@swiley countries typically don't let random noncitizens vote.
if heinlein's "you don't get to vote unless you were willing to die for it" is one direction, "you can vote as long as you got past the texas horseman" policy is the polar opposite
if heinlein's "you don't get to vote unless you were willing to die for it" is one direction, "you can vote as long as you got past the texas horseman" policy is the polar opposite