They are already backtracking
S&P Director: Downgrade Not ‘Catastrophic’ For U.S. Credit-Worthiness
http://www.huffingtonpost.com/2011/08/08/sp-director-reaction-credit-worthiness_n_920827.html
Well, of course, the “Downgrade” in and of itself is not catastrophic.
The reckless out of control spending that is the reason for the down grade is however is becoming catastrophic.