Ok but this was what I was getting at (This has more to do with owing tax before you renounce citizenship): Also, persons who wish to renounce U.S. citizenship should also be aware that the fact that a person has renounced U.S. citizenship may have no effect whatsoever on his or her U.S. tax or military service obligations (contact the Internal Revenue Service or U.S. Selective Service for more information).
That's why you would have sever all ties in the US, i.e. pull your kids out of their US school, sell your house, cancel all insurances, healthcare and other contracts, cancel your US bank account(s) etc. etc. Just because it's a PITA doesn't mean it's impossible.
Bottom line is that if you leave and don't fulfill your obligations you shouldn't plan on coming back, ever.
Giving up your passport isn't the hard part. Getting citizenship in the places you mentioned, is. Unless you know a secret way.