Stuff happens. Stuff has certainly happened to both the UK economy and the government’s fiscal position. What Alistair Darling delivered on Monday was not a pre-Budget report, but a crisis budget. He scrapped the hallowed rules of Gordon Brown, his predecessor. Profligacy has replaced prudence as the watchword. But, the chancellor would insist, it is profligacy with a purpose.

The government’s aim is to restore confidence in the economy. But it is also taking a huge gamble on its ability to sustain the confidence of investors. I believe it is right to do so. But nobody can know. The risk that these monstrous fiscal deficits – with public sector net borrowing forecast at 8 per cent of gross domestic product in 2008-09, falling to 2.9 per cent only in 2013-14 – will trigger a sterling crisis, a big sell-off of UK government debt, or both, is not small. The decision to raise the top rate of tax to 45 per cent for the first time in two decades is also symbolic. If 45 per cent today, why not 50 per cent tomorrow? This is a different country.