The Federal Reserve will print money to buy nearly as much U.S. Treasury debt in the next eight months as the U.S. government will issue.

The Fed's decision this week to buy $600 billion more of U.S. Treasury debt is setting off a debate about the risks of a central bank entwining its policies so tightly with the government's fiscal fortunes. The Fed is essentially lending enough money to the government to fund its operations for several months, something called "monetizing the debt."

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