The analogue of the 1929 Wall Street crash is not the 2007 credit crunch, but the bursting of the New Economy bubble in 2000. The follies of the 1990s resembled those of the 1920s...

In 1937-38, markets and business leaders came to doubt the durability of the business foundations on which partial recovery from the Great Depression had been built. In 2007-08, markets and business leaders came to doubt the durability of the financial foundations that had supported consumption and asset price growth after the New Economy fiasco.

Our capacity to learn from the Great Depression is limited because we do not know how economies would have evolved after 1938 if politics had not supervened.