Before the Iraq war began, Lawrence Lindsey, then president George W. Bush’s economic adviser, suggested that the costs might reach $200bn. The White House promptly fired him. Mr Lindsey was indeed wrong. But his error lay in grossly underestimating the costs. The administration’s estimates of a cost of some $50-$60bn were a fantasy, as were Saddam Hussein’s weapons of mass destruction, and much else.

An analysis by Linda Bilmes of Harvard University and the Nobel-laureate Joseph Stiglitz of Columbia University suggests that the administration underestimated the economic costs by considerably more than an order of magnitude.* To paraphrase erstwhile senator Everett Dirksen: “a $100bn error here, a $100bn error there and pretty soon you are talking real money”.