News broke that Societe Generale, the second largest French bank, recognised as a world leader in derivatives trading, had lost five billion euros on - wait for it - a rogue trader in derivatives.
It was a 'eureka' moment. The leaders of the world's banks woke up to the realisation that although they had devoted a vast amount of PR in recent months to reassuring the public about their financial soundness, they might be in trouble too - or more to the point, they could no longer expect to convince anyone else that they were not.
Financial houses have long understood that they are only as good as their reputation, because no-one puts money into a bank they do not trust.
Credit and reputation are in effect the two sides of the same coin, which is why HSBC and Citigroup have committed billions of pounds to rescue various structured finance vehicles with which their names were associated, although they had no legal requirement to do so. One that chose not to do so - Bear Stearns - has been in the dog house ever since.
But it is one thing to manage an individual reputation, it is quite another to manage a whole sector. The problem the banks face now is that they are damned by association. If Soc Gen did not know what was going on in the bowels of its own organisation - and it was feted as an industry leader - why should we believe any other banks when they tell us that there is nothing to worry about? The crisis in the credit markets stems from the fact that the banks will no longer lend to each other, and their reluctance is because they no longer trust each other. But if they do not trust each other, why should we?
Disunity is everywhere. And it shows how limited is the power of an organisation to manage its reputation in the short term, when the tide of opinion is so universally negative.
Perhaps in six months, when auditors have forced banks to disclose their bad loans, then the genuinely strong will stand out among the weak. Until then, the more banks protest their virtue, the more nervous their customers become.
Anthony Hilton is City commentator on London's Evening Standard