So I think you have a brand new United States.” That was Donald Trump’s boast in his speech to the business elite gathered at the World Economic Forum in Davos. So how, if at all, is America “new”? How might this belief of Mr Trump’s affect his global economic agenda? Why did Mr Trump, who shocked Davos, by stating at his inaugural that “Protection will lead to great prosperity and strength”, become only the second US president to visit the annual meeting in Switzerland, after Bill Clinton, in 2000?

Mr Trump’s main aim, it was clear, was to assert that “after years of stagnation, the United States is once again experiencing strong economic growth”. Moreover, it is “open for business”. These and similar claims on employment and consumer and business confidence ran through his speech. It is true that the US economy is strong; it is not true that this follows years of stagnation.

Between the second quarter of 2009 and the end of 2016, the US economy grew at a compound annual rate of 2.2 per cent. Over the past four quarters, it grew by 2.5 per cent. That is not a significant change. The big shift in growth — downwards, unfortunately — was after the financial crisis of 2008. The economy is 17 per cent smaller than it would have been if the 1968-2007 trend had continued. Since its recovery, in 2009, it has been on a far slower trend. This may change, but has not yet done so. The same is true for labour productivity, whose growth remains low. (See charts.)