The current crisis did not start on Wall Street.

Fortune managing editor Andy Serwer and writer Allan Sloan—the latter maybe the dean of U.S. financial journalists—argue in Time that Wall Street got tangled in complex investments that no one really understood. But the case can also be made that Wall Street understood its baroque instruments just fine, though clearly it underestimated the risks. What Wall Street may not have understood was just what a bad product the mortgage loans—which were the foundation of the boom and the driver of the crash—were.

You don't find Wall Street especially eager to own up to this: Who wants to admit that they were not, after all, the "smart money"? But all the evidence is that Wall Street saw this part a whole lot less clearly than did the mortgage brokers and commercial bankers-who were eager to go to Wall Street and palm their loans off on a greater fool. The bill of goods that Wall Streeters sold their clients had already been well-handled, and the smudged fingerprints on it belong to the bankers of "Main Street," those proverbial sheep who seem to have done a thorough job of shearing the wolf.