George Osborne is no longer chancellor, sacked by the post-Brexit Prime Minister, Theresa May. Philip Hammond, the new Chancellor, has yet to announce detailed plans but he has indicated that the real economy rather than the deficit is his priority. The senior Conservatives Sajid Javid and Stephen Crabb have advocated substantial increases in public-sector infrastructure investment, noting how cheap it is for the government to borrow. The argument that Osborne and the Conservatives had been making since 2010 – that the priority for macroeconomic policy had to be to reduce the government’s budget deficit – seems to have been brushed aside. Is there a good economic reason why Brexit in particular should require abandoning austerity economics? I would argue that the Tory obsession with the budget deficit has had very little to do with economics for the past four or five years. Instead, it has been a political ruse with two intentions: to help win elections and to reduce the size of the state. That Britain’s macroeconomic policy was dictated by politics rather than economics was a precursor for the Brexit vote. However, austerity had already begun to reach its political sell-by date, and Brexit marks its end. To understand why austerity today is opposed by nearly all economists, and to grasp the partial nature of any Conservative rethink, it is important to know why it began and how it evolved. By 2010 the biggest recession since the Second World War had led to rapid increases in government budget deficits around the world. It is inevitable that deficits (the difference between government spending and tax receipts) increase in a recession, because taxes fall as incomes fall, but government spending rises further because benefit payments increase with rising unemployment. We experienced record deficits in 2010 simply because the recession was unusually severe. In 2009 governments had raised spending and cut taxes in an effort to moderate the recession. This was done because the macroeconomic stabilisation tool of choice, nominal short-term interest rates, had become impotent once these rates hit their lower bound near zero.