Whatever the IMF thinks, we are a long way from the boom time of 2007 | Larry Elliott

Christine Lagarde may be optimistic about the global economy but there are good reasons why the heady growth seen before the financial crisis won't come back

When the International Monetary Fund met for its spring meeting in Washington 10 years ago the global economy was booming. The world was experiencing the strongest period of sustained growth since the late 1960s and early 1970s and the fund thought the good times would continue.

There was a bit of concern about the rip-roaring US housing market, but no suggestion that a crisis in the sub-prime mortgage market would be the catalyst for the biggest recession since the 1930s. Even when the trickle of foreclosures turned into a flood the assumption was that it was merely a localised problem that would soon be sorted out. Only when the entire global financial system froze up a year later did everything become horribly clear.

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