Trump's advisers later confirmed that neither the call nor the formulation were a mishap. A day later, Trump attacked China -- again on Twitter -- for devaluing their currency and building "a massive military complex in the middle of the South China Sea." His foreign policy philosophy may follow the credo of the American novelist Gore Vidal: "It's not enough that I should succeed, others should fail!"

Making America great again apparently means making others do badly. But will it work?

The one thing one could expect from a businessman like Trump is that he would run the numbers on the problem. They look challenging. For a decade, China has been growing faster than the US. In currency terms, US GDP in 2000 was 8.5 times that of China. In 2016 the difference has shrunk to less than 1.5 times. At this rate China will have overtaken the US in ten years (and it already has if you calculate GDP using purchasing power parity, which factors in the comparative value of money in different countries).