Are you a Marxist, a realist or a believer in the accident theory of history? Each school of thought suggests a different way of analysing the crisis in US-Chinese relations.

A trade war is well under way between the world’s two largest economies, and talk of a new cold war is now common in both Washington and Beijing. The two countries have just had a frosty and unproductive encounter at the Asia Pacific Economic Co-operation meeting. But, at the end of this month, Donald Trump and Xi Jinping, the presidents of the US and China, will meet at the G20 summit in Argentina for crucial talks that could culminate in a new deal on trade — or a further rise in tensions.

A Marxist might expect that business interests will prevail, and that, as a result, there will soon be a truce in the trade war between the US and China. A follower of the “realist” theory of international relations would assume that an established power like the US and a rising power, such as China, are inevitably going to clash — and that therefore economic and strategic tensions will keep rising. And somebody who thinks that history is driven by accidents will tell you that no theory can explain how things will pan out since so much depends on unpredictable human beings.