By just talking about adding stimulus at a slower pace, Federal Reserve Chairman Ben S. Bernanke sent bond yields a percentage point higher. The rout serves as a warning to monetary policy makers that their exit from record accommodation won't be easy to control.

The jump in yields has pushed up the cost of mortgages for millions of Americans, curbed demand for homes and prompted thousands of job cuts at Bank of America Corp. and Wells Fargo & Co., all at a time when the Fed's policies are aimed at creating jobs and supporting housing.

Bernanke has stressed that any reduction in the amount of money the central bank pumps into the financial system each month doesn't mean policy is getting any more restrictive. That message hasn't been heeded by bond investors, demonstrating how hard it will be for the Fed to control long-term interest rates as it moves toward tightening, according to Lou Crandall, chief economist at Wrightson ICAP LLC in Jersey City, New Jersey.