http://finance.yahoo.com/banking-budgeting/article/112189/who-owns-the-us?mod=bb-debtmanagement'While most of the country's $14 trillion debt is held by private banks in the U.S., the Treasury Department and the Federal Reserve Board estimate that, as of December, about $4.4 trillion of it was held by foreign governments that purchase our treasury securities much as an investor buys shares in a company and comes to own his or her little chunk of the organization.'
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4. Oil Exporters
Amount of U.S. debt: $218 billion
Share of total foreign debt: 5%
Another grouped entry, the oil exporters form another international bloc with money to burn. The group includes 15 countries as diverse as the regions they represent: Ecuador, Venezuela, Indonesia, Bahrain, Iran, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates, Algeria, Gabon, Libya, and Nigeria. As a group they hold 5% of all American foreign debt, with a combined $218 billion of U.S. treasury securities in their own treasuries. That's roughly equivalent to the combined 2009 GDP of Nebraska ($86.4 billion) and Kansas ($124.9 billion), which seems to be an equal trade: The two states produce a bunch of grain for export, which many of the arid oil producers tend to trade for oil.
6. Caribbean Banking Centers
Amount of U.S. debt: $155.6 billion
Share of total foreign debt: 3.6%
You have to have cash on hand to buy up U.S. government debt, and offshore banking has given six countries the combined capital needed to make the Caribbean Banking Centers our sixth-largest foreign creditor. The Treasury Department counts the Bahamas, Bermuda, the Cayman Islands, the Netherlands Antilles, Panama and the British Virgin Islands in this designation, which as a group holds $155.6 billion in U.S. treasury securities. That's equivalent to the GDP of landlocked Kentucky ($156.6 billion), whose residents may not actually mind if they were ever to become an extension of some Caribbean island paradise.
This info is handy if we ever have to make that dreaded "The check is in the mail" phone call.