Reaching the debt limit just means the federal government cannot borrow more. The government can still roll over debt and cover any debt that becomes due with new borrowing, which would not require increasing the total outstanding national debt.

The federal government could even easily continue to pay any interest due on that national debt, without increasing the debt limit. That is because federal tax revenue would continue to roll in as required by law. President Obama’s own 2012 budget specifies net interest spending for this year at $206.7 billion. But individual and corporate incometaxes, and excise taxes, for the year are estimated to be over 6 times as much, at $1,257.5 billion, or $1.3 trillion.

Also continuing to flow in would be Social Security payroll taxes. Social Security is implicated in the debt limit fight because the so-called Social Security “trust funds” are rightly counted as part of the national debt subject to the debt limit. All the government bonds in those trust funds are just a statement of the legal authority that Social Security has to draw from general revenues, in addition payroll tax revenues, to pay Social Security benefits.

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I just wish Washington would stop playing games.