Original links are included though some may have expired.

The Numbers:

Treasury securities held by foreign governments and banks,
April 2001: $0.975 trillion

Treasury securities held by foreign governments and banks,
October 2005: $2.102 trillion

What They Mean:

This year's American budget deficit will be around $360 billion - a figure roughly equal to the GDP of middle-sized countries like Australia or the Netherlands. To cover the gap, each month the Treasury Department sells bonds and T-bills. Foreign central banks and private financial institutions buy many of these securities, in return for interest payments or later redemption at higher values. Together, they hold about $2.2 trillion worth of American government securities; foreign governments account for $1.25 trillion of the total and private financial institutions a bit more than $900 billion.

This figure, rising by about a quarter-trillion dollars a year, has more than doubled since 2001. In the late 1990s and 2000, it was dropping steadily as the government ran surpluses and paid off older bonds and Treasury bills. The low point came in mid-2001, when foreigners held $975 billion in Treasury securities. This was the equivalent of about 9.6 percent of the 2001 GDP. After the 2001 and 2003 tax bills, structural deficits returned and trends went into reverse. The Treasury Department began selling securities again, and liabilities accordingly began to rise. The $2.2 trillion worth of outstanding securities now amounts to nearly 17 percent of GDP.

Japan is the largest single holder of these securities, with $682 billion as of October 2005, and also their fastest-growing holder in absolute terms, with holdings up from $317 billion in mid-2001. China is the second-largest holder, with $248 billion, and also the fastest-growing major T-bill holder in percentage terms over the past four years. (The holdings rising from $74 billion in mid-2001. The UK is third with $187 billion, and was the fastest accumulator of US government debt in 2005. Taiwan, Germany, Korea, Canada and Hong Kong also hold $50 billion or more in U.S. securities; OPEC nations together hold $65 billion and Caribbean banking centers $113 billion.

Further Reading:

PPI offers fifty ways to cut deficits:
http://www.ppionline.org/ppi_ci.cfm?knlgAreaID=125
&subsecID=162&contentID=252356

The Treasury Department lists its creditors:
http://www.treas.gov/tic/mfh.txt for 2005 and:
http://www.treas.gov/tic/mfhhis01.txt for 2000-2004.

America's top two creditors: