“Financial markets have long treated U.S. bonds as the ultimate safe asset; the assumption that America will always honor its debts is the bedrock on which the world financial system rests. In particular, Treasury bills — short-term U.S. bonds — are what investors demand when they want absolutely solid collateral against loans. Treasury bills are so essential for this role that in times of severe stress they sometimes pay slightly negative interest rates — that is, they’re treated as being better than cash.

”Now suppose it became clear that U.S. bonds weren’t safe, that America couldn’t be counted on to honor its debts after all. Suddenly, the whole system would be disrupted. Maybe, if we were lucky, financial institutions would quickly cobble together alternative arrangements. But it looks quite possible that default would create a huge financial crisis, dwarfing the crisis set off by the failure of Lehman Brothers five years ago.

“No sane political system would run this kind of risk. But we don’t have a sane political system; we have a system in which a substantial number of Republicans believe that they can force President Obama to cancel health reform by threatening a government shutdown, a debt default, or both, and in which Republican leaders who know better are afraid to level with the party’s delusional wing.”

-- Paul Krugman, “Rebels without a Clue,” NY Times.