As Trump turns his back on the world, the stage is set for President Xi | Larry Elliott

The newly emboldened Chinese leader will exploit US isolationism, giving America its first serious challenge since the collapse of the Soviet Union

It was a symbolic moment. High in the Swiss Alps, before an audience of the super-rich gathered for their annual shindig in Davos, China's Xi Jinping delivered a powerful defence of globalisation. Protectionism, he said, was like locking yourself in a dark room. "While wind and rain may be kept outside, that dark room will also block light and air."

On that January day nine months ago, the target for Xi's comments was more than 4,000 miles away on the other side of the Atlantic, preparing for his inauguration as president a couple of days later. The message was simple: if Donald Trump is going to turn his back on the world, China will fill the vacuum.

The US has its weaknesses too, and Trump's tough guy act should fool nobody. It is unlikely to impress Xi

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