From The Annals Of Sane Conservatism I

Gulp:

What happens if we crash into the debt ceiling? Nobody really knows, but it’s not likely to be pretty. Inflows and outflows of cash to and from the Treasury jump around from day to day as bills are paid and revenues arrive. But at average fiscal 2011 rates, receipts cover only about 60% of expenditures. So if we hit the borrowing wall traveling at full speed, the U.S. government’s total outlays—a complex amalgam that includes everything from Social Security benefits to soldiers’ pay to interest on the national debt—will have to drop by about 40% immediately.