Actually, the US government is behaving very rationally. Realizing the pressure on the US dollar, especially since progress is already happening in moving to SDRs (special drawing rights) as the world's reserve "currency" and trading blocs are increasingly using their own currency for bilateral trade.

President Clinton signed a bill that confiscates part of someone's net worth over a threshold for renouncing US citizenship and moving to another country. Bush and Obama are taking similar steps to keep assets in the USA. While it is reasonable to go after money laundering, it is becoming increasing difficult to do some business transactions internationally, open bank accounts in countries where one spends a lot of time on vacation or has residency, etc.