"Congratulations. Now don't screw up." The legendary greeting meted out by Goldman Sachs elders to new recruits encapsulates the mixture of confidence and anxiety at the heart of Wall Street.

For all their greed-is-good paeans to unbridled competition and ever more daring deals, the pinstriped alpha men and women inhabiting New York's skyscrapers live in constant fear of failure. History makes sure of that.