Could the U.S. central bank go broke?

With the U.S. unemployment rate at 9.4 percent and only tentative signs that businesses are beefing up hiring, Fed officials, including Chairman Bernanke, see a duty to prevent a further deterioration of economic conditions -- and have signaled a readiness to use all the tools at their disposal.

Last November, as the economic recovery appeared to falter, the Fed said it would buy a new round of $600 billion in Treasury securities through June of this year. That's on top of the $1.7 trillion in Treasuries and mortgage-backed securities it had purchased in response to the financial crisis.

http://www.reuters.com/article/idUSTRE7096FE20110111?pageNumber=2