The subprime saga is far from over. The markets remain on high alert. Each day seems to bring new rumors or announcements of losses. A golden age for banks and brokers has come to a sudden end.
The moral is clear. When Wall Street appears in genius mode, raking in huge profits on mysterious products and complex trades, the secret isn't genius at all. It's that hubris is running wild, and so is risk. And whether it's tomorrow or five years hence, risk will jump from the shadows, knife in hand, to cut genius down to size.
By Shawn Tully, Fortune editor-at-large