Moody's says tax cut deal risks U.S. credit rating

Hess writes that the higher economic growth from the tax cuts and unemployment benefits might be substantial, but the effect of the growth on budget deficits will be less than the effect of the foregone revenue and increased spending.

He notes that the Congressional Budget Office has found that the package would raise the ratio of debt-to-gross domestic product from 61.6 percent to 68.5 percent by 2012.

This ratio would be worsened if the tax cut package is extended in 2012, something that is highly possible in an election year, the report notes. It says that the president's debt commission developed a plan to deal with the budget crisis but adoption of the plan is "uncertain."