> Are you suggesting that we should have interstate border controls, and require Americans traveling from one US state to another to obtain a visa first?
Are you suggesting that US borders with Canada and Mexico, as well as our maritime borders, should be as open as the borders between states?
I'd like to move in the direction of eliminating them, yes. I don't see any reason to keep US/Canadian border controls, given that the relative parity of incomes means there isn't likely to be some huge, destabilizing migration. The EU's Schengen free-travel zone is a good precedent to follow on that, imo. Mexico is a harder case because of how screwed up the country currently is; opening borders tends to work better between relatively stable countries. But certainly we could start with Canada.
I think you should answer my question first, since the existence of interstate crime is indisputable and this doesn't seem qualitatively different from the deleterious effects which you are citing in the Cuban example.
But yes, I think we should be moving towards abolition of external border controls over the long term and dissolution of geographic borders with immediate neighbors like Mexico and Canada in the short term.
Even if we accept this premise, however, the same situation applies within the United States. Many people commit crimes in one state and later move to another, where they may or may not commit further crimes. This is such a widespread phenomenon that there's a constitutional clause requiring courts in each state to give 'full faith and credit' to courts in other states, so that criminals can't escape justice by just hopping over the nearest state border. Are you suggesting that we should have interstate border controls, and require Americans traveling from one US state to another to obtain a visa first?