about 2/3 down the page you’ll come to :
We must separate the risk of politicians acting childishly (extremely high) from the risk of the United States actually defaulting on its debt (extremely low).
Ironically, the political gridlock that caused the downgrade may actually help to reduce our debt. David Leonhardt remarked in the New York Times that if Congress remains deadlocked and cannot agree on a new tax policy, then the Bush tax cuts will automatically expire across all tax brackets on January 1, 2013. According to Bloomberg, this “amounts to a $3.6 trillion tax increase over 10 years,” roughly four times more than the debt deal negotiated between Democrats and Republicans. In other words, the political gridlock that Standard & Poor’s considers a major factor in our downgrade might be a major factor in righting our ship.