Consider https://en.bitcoin.it/wiki/Trade. When you scroll down a ways, you will find dozens (is it hundreds?) of places using Bitcoin like money. Once bread and butter living commodities are traded Bitcoin-wise, and people drop their bank accounts and their SSNs (so that Government no longer has authority over them by quasi-contract), ways will be found to stay in (not within) the country... or move out of it freely.

The police state is in place.  Now all it takes is the mob clamoring for a strong ruler to lead us out of our mess.  Where will the next Adolph Hitler come from?  How soon will he get here?   

I don't know but I do know the next Hitler will command nukes.  Not good and where are you going to escape that?