For years, people had warned that New Orleans was vulnerable - but when a hurricane came close to destroying the city, the reaction was muted. Some people took the near miss as a warning - others, as confirmation that there was nothing to worry about.

So why do we struggle to prepare for disasters? And why don't we draw the obvious lessons from clear warnings?

Sources for this episode include Amanda Ripley's The Unthinkable, The Ostrich Paradox by Howard Kunreuther and Robert Meyer, Margaret Heffernan's Willful Blindness, and Predictable Surprises by Max Bazerman and Michael Watkins. For a full list of sources see http://timharford.com/

Tim's latest books 'Fifty Inventions That Shaped The Modern Economy' and 'The Next Fifty Things That Made The Modern Economy' are available now.