We are at just such a moment again. Little more than two years ago, global leaders were happily congratulating themselves on having avoided the mistakes of the 1930s, thereby averting a depression. But now it appears that the difficulties of 2008 were but a foretaste of what was to come. With the European banking system again on the verge of collapse, there is a sense that politicians and economists are out of options, that governments and central banks are powerless before events. The best of the cavalry has been sent into battle, and it has come back in tatters. The fiscal armoury has been exhausted, the support offered by the boom in emerging markets such as China and India over the past two years seems to be on its last legs, and there is but the small rifle fire of the central bank printing presses left to defend us.