"I pledge to every citizen of our land that I will be president for all Americans."

The businessman turned TV star turned-politico -- who has never before held elected office -- will become commander-in-chief of the world's sole true superpower on January 20.

The results prompted a global market sell-off, with stocks plunging across Asia and Europe and billions being wiped off the value of investments.

Although he has no government experience and in recent years has spent as much time running beauty pageants and starring in reality television as he had building his property empire, Trump at 70 will be the oldest man to ever become president.

Yet, during his improbable rise, Trump has constantly proved the pundits and received political wisdom wrong.

Opposed by the entire senior hierarchy of his own Republican Party, he trounced more than a dozen better-funded and more experienced rivals in the party primary.

Trump refused to release his tax returns.

But the biggest upset came on Tuesday, as he swept to victory through a series of hard-fought wins in battleground states from Florida to Ohio.

Legacy of ashes 

Clinton had been widely assumed to be on course to enter the history books as the first woman to become president in America's 240-year existence.

Americans have repudiated her call for unity amid the United States' wide cultural and racial diversity, opting instead for a leader who insisted the country is broken and that "I alone can fix it."

If early results hold out, Trump's party will have full control of Congress and he will be able to appoint a ninth Supreme Court justice to a vacant seat on the bench, deciding the balance of the body.

So great was the shock that Clinton did not come out to her supporters' poll-watching party to concede defeat, but instead called Trump and sent her campaign chairman to insist in vain the result was too close to call.

"I want every person in this hall to know, and I want every person across the country who supported Hillary to know that your voices and your enthusiasm mean so much to her and to him and to all of us. We are so proud of you. And we are so proud of her," chairman John Podesta told shell-shocked supporters.

On the eve of the election, he told tens of thousands of people in Philadelphia that he was betting on the decency of the American people.

"I'm betting that tomorrow, most moms and dads across America won't cast their vote for someone who denigrates their daughters," Obama said.

"I'm betting that tomorrow, true conservatives won't cast their vote for somebody with no regard for the Constitution," he added.

His bet appears to have been flat out wrong, and America's first black president will be succeeded by a candidate who received the endorsement -- albeit unsought and unacknowledged -- of the white supremacist Ku Klux Klan.

Trump's shock victory is just the latest evidence that globalization has eroded faith in liberal political leadership.

From Britain's vote to leave the European Union to the rise of far right populists and nationalists in continental Europe, opposition to open trade and social and racial tensions are on the rise.  -AFP