Personally I think this is a mistake.
Things are bad in the US and getting worse but most everywhere else is even poorer shape.
The economic system is the same or worse elsewhere and the US has the advantage of
1) Strong libertarian movement
2) Guns
3) A good constitution. Yes its not enforced but its better then nothing.
The US will be the last to suffer from the coming debt collapse and likely among the first to bounce back and recover.
don't forget
4) Hydrocarbons in the form of oil, coal, and natural gas, plus plenty of gold, silver, copper, nickel, and platinum mines
5) Farmland, fresh water, tractors, and lots of Ford pick-up trucks
6) A military with Area 51 gear that can destroy all the other ones combined
7) We own the Moon