Fear and loathing require a tangible enemy. It is hard to stay angry at impersonal economic forces such as globalisation. The relative rise of regional powers around the world over the past decade - and the consequent relative diminution in the power of the still formidable West - are now a fact of life, but one so huge that threatened members of the American middle class cannot fasten upon it as the cause of their unease that the way of life they cherish may be passing.

No, far better to give their angst a clear, identifiable name; let's call it China.

So when the populists of the American right (think Donald Trump) or the left (conjure up Bernie Sanders) start bloviating irrationally about Beijing, the key thing to keep in mind is that it is not really China itself they are decrying as the root of all evil threatening the American Dream. Rather, "China" has become shorthand for globalisation, increased economic competition, and the birth of a multipolar world, where America remains first amongst equals, but can no longer alone simply call the shots.

For the 25 per cent of the American right and the 15 per cent of the left (based on current presidential polling) who are populists, someone, somewhere must be held accountable for the increased insecurity of the American middle class, for the death of the sunny and secure jobs-for-life system that buttressed American life after the second world war.

In the present iteration of global capitalism, an American high school diploma means next to nothing, working with your hands as opposed to your head consigns you to a life of economic struggle, and the United States must of necessity work with other great powers in the world - as the aftermath of the Lehman Brothers crisis made so very clear - to keep the global system afloat.

This is profoundly, and understandably, disorienting. Rather than come to grips with a new, more challenging world not to their liking, some have found it easier to blame "China". It is sadly unsurprising that the present crop of Republican presidential candidates have followed this fruitless intellectual path of least resistance.

Among the present Republican field, it is Donald Trump's feverish vision that most tracks the country's fears. Photo: AFP

By telling the frightened American middle class precisely what they want to hear - that there are simple solutions to their complicated problems - the present GOP field has yet to distinguish itself. Of the lot of them, it is Trump's feverish vision that most tracks the country's fears, implying that all present economic ills come down to America's gullible leaders.

To hear Trump tell it, American politicians (a hated class at present) have been simply hoodwinked by Beijing's more savvy leadership; America has been unfairly taken advantage of by our nefarious foes. Trump asserts that once he is president, he will simply summon business titans like Carl Ichan to negotiate with the Chinese and then America's economic problems will be all over. The grown-ups will come to the rescue. China will be brought to heel, and America's glorious economic past will be magically restored.

Trump speaks at a campaign rally aboard the USS Iowa in Los Angeles. Photo: AFP

Trump's fairy tale - of foolish American politicians, nefarious Chinese foes and a would-be hero unafraid to take on both - is carefully calibrated to appeal to America's restive middle class. While a wonderful bedtime story, such a tale has almost nothing to do with present realities.

The problem with the present China-bashing populism is that it encourages American public opinion to assume that the rise of China is the problem, rather then serving as part of the solution to the present global economic downturn. Given the desperate scarcity of worldwide growth, the international economic system needs the US, China and India to drive the global economic engine, even as emerging markets and Europe founder.

All true American grown-ups must shout down this dangerous nonsense at every turn, or US-China relations will become so poisoned that their vital cooperation will be endangered in the real world.

Dr John C. Hulsman is a life member of the Council on Foreign Relations and president and co-founder of John C. Hulsman Enterprises. www.john-hulsman.com