Alternate headline: “Feds leave dead fish on S&P’s doorstep.” And if you think this is shady, check out how Italy handled its own threat of a downgrade from S&P. Good lord. What happens if they downgrade Egypt? Does David Beers end up in the cage with Mubarak?

Note to Fitch from the Senate Banking Committee: Choose wisely.

Following S&P’s Friday night decision to reduce the nation’s credit standing from AAA to AA+, the panel has begun gathering information about the downgrade, according to a committee aide. Reuters first reported the committee’s interest in the downgrade.

The unprecedented downgrade of the nation’s debt roiled financial markets Monday, and S&P was subject to fierce criticism from Senate Banking Committee Chairman Tim Johnson (D-S.D.).

“As the financial markets stumble, investors continue to regard Treasury debt as a safe haven in times of economic uncertainty. This irresponsible move by S&P may, however, have spillover effects that tax the American people by increasing interest rates on home loans, credit cards, and car loans, and by increasing the cost of finance for some state and local governments,” he said in a Monday statement. “I am deeply disappointed in S&P’s decision to enter into the game of political punditry.”

No word yet on whether they’ll hold hearings. One minor caveat to this: What if S&P’s decision to downgrade really was shady? Fiscal conservatives spent the weekend defending the agency from leftist attacks out of simple gratitude, I think, that someone somewhere with some real market influence was finally ringing the alarm bell about our insane debt. We have $211 trillion in unfunded liabilities and yet Democrats are set to run on a “hands off my Medicare” platform next year. Don’t shoot the messenger for daring to suggest that this might, perhaps, be unsustainable, n’est-ce pas?

But what if the messenger was prepared to say that it is sustainable if not for their own dopey math error? That is to say, as Erick Erickson puts it, what if Obama’s right about S&P?

S&P, I’m told, began telling some of its clients about the downgrade on Friday morning. That’s why the market was so screwed up on Friday.

By Friday afternoon, the Treasury Department told S&P it had made a $2 trillion math mistake.

But S&P had already told its clients about the downgrade. So it couldn’t walk it back now without a major loss of confidence in its credibility. Could you imagine that conversation? “Hey . . . um . . . Joe. Yeah, Charlie here from S&P. So . . .um . . . we made a $2 trillion math mistake in our downgrade analysis. . . . What’s that? You just lost $500 million in the market because of it? Oh . . . um . . . sorry Joe. Better luck next time.”

So it had to come up with a different reason.

It’s reason? Acrimony in Washington — in other words, nothing to do with the U.S.A.’s ability to pay its debts or financial issues, just typical Washington politics.

It’s possible to believe that the U.S. deserved to be downgraded in the abstract but that the U.S. didn’t deserve to be downgraded according to S&P’s lame criteria, especially if they botched their calculus and went through with the downgrade to protect their reputation. To see just how lame they are, in fact, read Nate Silver’s user-friendly statistical analysis of how S&P rates other sovereign debt. Not only do they perceive genuine default risks more slowly than the market, they’re slow to accurately rate a given country’s default risk when they finally do perceive it. They’re a lagging indicator, in other words — except, oddly, in the case of the U.S., where they’re out in front of the pack in declaring us a credit risk even as investors around the world continue to plow money into treasuries. Very curious. That’s not to say they deserve a congressional investigation, but a little more public attention to how arbitrary the ratings agencies are might stave off the next market panic.

Via News Busters, here’s Scarborough asking Democrats to quit using the tea party as a downgrade pinata. To which Debbie Downer says: No dice. Exit question via NRO’s Andrew Stiles: How can tea partiers be responsible for the downgrade when liberals have spent 48 hours insisting that the downgrade never should have happened?