4 March 1933: FDR takes office as the banks close

Franklin Roosevelt was inaugurated amid a banking panic, telling Americans the only thing they had to fear was fear itself. The New York Stock Exchange did not open that day as banks across the country closed their doors. Within two days Roosevelt declared a national bank holiday. The Dow, which had lost nearly 90% from its 1929 peak, would soon stage a spectacular rebound.

The lesson: The darkest moments of a crisis are often when the foundations for recovery are being laid.