The future of our world heavily depends on relations between the US, a new country and the incumbent superpower, and China, an ancient empire and a rising superpower. Making these relations particularly challenging have been the election of Donald Trump, a populist xenophobe, in the US, and the ascendancy of Xi Jinping, a centralising autocrat, in China.

No less contrasting, however, are the perspectives of these two on the world economy. Forty years ago, Mao Zedong ruled China: his aim was autarky. Ever since 1978, however, the watchword of China’s economic policy has been the “reform and opening up” proposed by his successor, Deng Xiaoping. Meanwhile, the US, progenitor of post-second world war liberal internationalism, is consumed with self-doubt and so has elected as leader a man who considers this outstandingly successful policy inimical to his country’s interests.

One of today’s ironies is this reversal of attitudes towards the open world economy. Nothing better illustrates this than the contrast between the strong support for globalisation offered by President Xi at the World Economic Forum annual meeting in Davos in January and Mr Trump’s egregious assertion, just three days later, that “Protection will lead to great prosperity and strength”. The communiqué of the meeting of the Group of 20 finance ministers in Germany last weekend duly dropped last year’s language vowing to “resist all forms of protectionism”. The implications of such US protectionism are still unknown. But they are highly disturbing. The very last thing our fragile world economy needs is a trade war between the US and China.