The US is a tax haven for the worlds rich and this is a good thing. It keeps the $ as the worlds preferred global currencyAnd allows Americans to basically enjoy free money by borrowing $ at virtually no cost

[outsourci...@yahoo.com]

If the US would go after those who put their money in the US the strength and resilience of the dollar would decline and the easy money that Americans enjoy would end.
Therefore the amounts lost to the US GOVT in losing some tax revenue is insignificant. There are multiple benefits of the US being this safe haven for rich people the world over.
If this would end the sheen of the US dollar as being the worldwide currency would lose importance leading to a massive drop
in the demand for US TREASURY BONDS and the easy free money the Americans enjoy today at virtually no cost to them.
If people thecworld over stopped their love for American dollars the party would be over for all Americans.