It took a viral invasion to unmask the weakness of American finance. Distortion in the cost of credit is the not-so-remote cause of the raging fires at which the Federal Reserve continues to train its gushing liquidity hoses.

But the firemen are also the arsonists. It was the Fed’s suppression of borrowing costs, and its predictable willingness to cut short Wall Street’s occasional selling squalls, that compromised the U.S. economy’s financial integrity.

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