It’s easy to get yourself into a corner if you make decisions without a sound basis. More than that, it’s really hard to change your mind if there was never a basis for the decision in the first base. Or if you don’t want to be honest about what the basis is.
What am I on about? The S&P’s downgrading of the US was political not economic. Whatever credibility they have left after the AAA rating of defaulting (and inherently likely to default) CDOs is now gone.
Yes, much of this comes from Paul Krugman. I don’t pretend to understand the US budgeting process (yet) but at least I know that I don’t know.