Standard & Poor’s has been wrong before. But they’re right now.

Standard Poor’s decision to downgrade the United States has led to a lot of criticism of Standard Poor’s. The White House called their performance, which included a miscalculation of about $2 trillion, “amateur hour.” Rep. Barney Frank was even less sparing. “These are some of the people who have the worst records of incompetence and irresponsibility around,” he told Rachel Maddow last night. They are trying to “justify their reputation.”

All of this is true. Standard Poor’s didn’t just miss the bubble. They helped cause it. They were paid by the banks to award their AAA-stamp of approval to all manner of financial products that were anything but riskless -- which, ironically, makes them an accessory to the resulting explosion of U.S. debt. You’ve heard the old joke about chutzpah being a young man who murders his parents and then pleads for leniency because he’s an orphan? S&P has chutzpah. All the credit-rating agencies do. It’s built into their business, which requires them to assess the stability of markets they helped crash. It’s long been my position that the credit-rating agency model is broken and, at times, dangerous, and investors need to pay less attention to their pronouncements.

But that doesn’t make Standard Poor’s wrong in this particular case. “The downgrade reflects our view that the effectiveness, stability, and predictability of American policymaking and political institutions have weakened at a time of ongoing fiscal and economic challenges,” they explained in the statement accompanying Friday’s decision. After Republicans in Congress spent three months weighing whether or not to default on our debt and Senate Minority Leader Mitch McConnell said that paying our bills would never again be a foregone conclusion, can anyone really argue with that? After every Republican presidential candidate save Jon Huntsman either remained silent on, or flatly opposed, the deal to raise the debt ceiling, can anyone really say that U.S. debt is completely riskless? That there’s no chance of a political miscalculation, and if there is such a chance, that they can perfectly predict the outcome of the ensuing chaos?

In Washington, it’s almost trite to say that the political system is broken. It’s been clear for some time that things really are different, that norms and procedures that once kept fractious congresses functioning have eroded with terrifying speed. If anything, S&P is, as usual, noticing the deterioration too late. But that doesn’t mean the deterioration is not real, or that it should be ignored. Too often, the pressure in Washington is from interest groups and activists and political consultants who are, perhaps without meaning to, pushing towards further dysfunction. Those of us in Washington who would like to see the government work have long wondered when the business community and other entities who need a functioning political system would begin exerting a countervailing force. Perhaps it begins now. If not, then this may be the first of many downgrades to come.