Theoretically, they can lock you out by suspending your passport and preventing you from traveling even if you leave the country. Also they can have full access to your bank records given the warrant and you can't make any serious purchases with cash.
Even in an unlikely apocalyptic scenario you have described they won't gain much more power than they already have. I don't see how this makes you a slave by itself. Only if government begins using this as a tool to control you but then, if we hit such a point, they have much more other tools people have to worry about.
Even in an unlikely apocalyptic scenario you have described they won't gain much more power than they already have. I don't see how this makes you a slave by itself. Only if government begins using this as a tool to control you but then, if we hit such a point, they have much more other tools people have to worry about.