Donald Trump’s victory marks a thunderous repudiation of the status quo. The most powerful nation on earth has elected a real estate developer with no experience in government, a self-styled strongman contemptuous of allies, civil discourse and democratic convention. Barring a protean change of personality, Mr Trump’s victory appears to represent a challenge to the western democratic model.

In 2016, Americans preferred a political neophyte with a simple slogan, “Make America Great Again”, to a candidate who has served as First Lady, senator for New York and secretary of state. Democrats will be tempted to blame their defeat on Mrs Clinton’s soulless campaign, with a mortal blow delivered by the FBI’s late intervention in the saga of Mrs Clinton’s use of a private email server.

This conveniently ignores the Republicans’ clean sweep of the House, Senate and White House — a rebuff not just to Mrs Clinton but also to President Barack Obama, who put his reputation and his legacy on the line in the lastdays of the campaign. Excuses also ignore the profound faultlines in American society exposed by the global financial crisis.

Mr Trump’s campaign appealed to nativism, isolationism and protectionism. He railed against immigrants and vowed to build a vast wall to keep them out, at Mexico’s expense. He castigated allies in Europe and Asia, disavowing decades of foreign policy doctrine by suggesting Japan and South Korea could go nuclear to counter security threats from China. He cosied up to Vladimir Putin, coming close to being an apologist for the Kremlin. And he pledged to tear up trade agreements such as Nafta and the Trans-Pacific Partnership in order to protect and reclaim American manufacturing jobs.

Mr Trump’s sweeping rhetoric and compulsive tweeting resonated among millions of Americans who have felt marginalised by globalisation. The free movement of capital, goods, labour and services is one of the great achievements of the postwar era. Globalisation has lifted millions out of poverty, especially in Asia. In the US, as told by Mr Trump, globalisation and free trade have rewarded a privileged few. Inequality has risen, median incomes have stagnated or fallen in real terms in recent years, especially among the uneducated or undereducated with no college degree.

There is, of course, an alternative narrative that highlights the inherent resilience of the US economy, its capacity to innovate and produce world-class winners, especially in technology epitomised by Silicon Valley. But Mrs Clinton, remote and often robotic, failed to counter with a compelling vision of change.

What, then, are the prospects for a Trump presidency? The optimistic view is that the mean-spirited, Muslim-baiting candidate will transform once inside the White House. Such a change looks improbable, at this stage. His temperament may not allow it. He can also argue, justifiably, that his tactics, however outrageous won him the presidency. He had a chance to pivot toward a more responsible middle ground after the Republican convention and he chose not to do so.

Mr Trump might nevertheless reflect that his victory does give him a second chance. He has to pick a team to carry out his agenda. He must work with Congress, notably Paul Ryan, the House speaker, whom he has regularly derided. Mr Trump prides himself on understanding “the art of the deal”. He must realise that the business of government cannot be driven by personal feuds. Politics in a democracy is the art of compromise.

The world will be nervously watching Mr Trump’s first moves. So will financial markets, which have taken initial fright. This is a moment of great peril. Mr Trump’s victory, coming after the Brexit referendum vote in Britain, looks like another grievous blow to the liberal international order. Mr Trump must decide, by his actions and words, whether he intends to contribute to the great unravelling, at incalculable cost to the west.