These are fair points, all of which I think could be addressed by finding the optimal taxation point. The keyhole solution I favor would be something like: a U

These are fair points, all of which I think could be addressed by finding the optimal taxation point. The keyhole solution I favor would be something like: a US passport for 10 years, with no political rights or access to SS/Medicare/medicaid/etc., costs $10k, if you lived here for 10 years and didn't get arrested or anything then that transitions into full citizenship; maybe if you earned a certain amount of money/paid a certain amount of taxes in that time, you get your 10k back. Something like that, anyway. (FWIW my first choice would be a much, much lower barrier to entry -- this is what I came up with to try to address concerns like those raised in this thread.) But, again, if you accept that the default moral position is non-violence -- i.e. people have a prima facie right to move where they want, and if you threaten to hurt them for doing so (by putting them in jail, or making the only available border crossing extremely dangerous), then you are acting wrongly -- then I think it becomes natural to begin looking for solutions to whatever externalities you can think of. That's why I favor arguing the moral case for immigration before anything else: http://www.owl232.net/papers/immigration.htm http://www.owl232.net/papers/immigration.htm