The United States is a haven for people from all over the world who come to the United States for the American way of life from a foreign country.
Many of these individuals have accumulated wealth and accumulated income which they have paid little or no taxes. In the event these individuals do not plan properly, their accumulated wealth and accumulated income could be subject to United States taxes after they have become United States taxpayers.
There are several techniques to insure that accumulated wealth and income earned prior to becoming a United States taxpayer can be protected from United States taxes.
This requires planning in advance by non-resident alien individuals who will become United States taxpayers. These techniques are described in this segment on pre immigration tax planning.