DONALD TRUMP has produced a veritable blizzard of trade tariffs across most industrial sectors and countries, rowing back, reducing, delaying and re-applying them, not so much where other countries have prejudiced US goods but where countries simply have a balance of payments surplus with the USA – or, in the case of the UK, even a deficit! It has caused chaos for the massive integrated supply chains, mainly organised by American companies to buy cheap in China and Southeast Asia and sell...