The Land of the Free is starting to look ungovernable. Enough is enough … America enjoys the “exorbitant privilege” of printing the world’s reserve currency. Its government debt is considered a safe haven, which is why Uncle Sam can borrow so much, so cheaply. America will not lose these advantages overnight. But anything that undermines its creditworthiness—as the farce in Washington surely does—risks causing untold damage in the future. It is not just that America would have to pay more to borrow. The repercussions of an American default would be both global and unpredictable. … It would threaten financial markets. Since American Treasuries are very liquid and safe, they are widely used as collateral. They are more than 30% of the collateral that financial institutions such as investment banks use to borrow in the $2 trillion “tri-party repo” market, a source of overnight funding. A default could trigger demands by lenders for more or different collateral; that might cause a financial heart attack like the one prompted by the collapse of Lehman Brothers in 2008. In short, even if Obamacare were as bad as tea-party types say it is (see Lexington), it would still be reckless to use the debt ceiling as a bargaining chip to repeal it, as some Republicans suggest.