Women supporters cheer Donald Trump as he speaks at a rally in Cleveland, Ohio

We are told every time that the outcome will affect us all. This time it really will.

The decision taken by American voters will have implications for all of us for years to come.

The post-war world order that has guaranteed our security and prosperity for decades could be at stake.

Donald Trump has shown little interest in the institutions painstakingly set up after World War Two and spoken blithely of ripping up trade agreements and undermining western alliances.

If he wins today, the world we have grown up taking for granted could be in jeopardy.


"It could be that he puts a nail in the coffin of the North Atlantic Alliance," former British ambassador to the US Sir Christopher Meyer told Sky News.

Sarah Palin: 'Britain and the US are going rogue'

Mr Trump has thrown into doubt America's automatic support for any NATO ally if it fails to pay its dues.

Sir Christopher said: "He's already said if that state in his view is not paying its dues to the NATO budget then Article 5 will be suspended.

"That is truly a nail in the coffin of the post-Second World War international order."

Never before has a US election prompted sober-minded commentators to predict the possible end of western civilisation.

But in a recent doom-laden article, the FT's Chief Economics Commentator Martin Wolf wondered if "the West might soon be lost".

He told Sky News: "If things are to go extremely badly, the global economy goes into a global recession because of the trade wars he launches, lots of the debt in the world collapses because everyone has lost faith in the underpinnings of the global economy and we're back in the 30s.

"I don't think we have ever seen a candidate emerging of this kind in the US, actually really ever.

"Certainly since it's been a great power. And I think we are right to be worried about the potential implications of this transformation of the basis of American democracy."

Clinton voters on Women for Trump

What's also at stake is the credibility of American democracy. Americans are brought up believing their country and its form of government are exceptional.

Their founding fathers thought they were creating a new form of government that would be an example for other countries to follow. Every American child is taught to believe that in school.

And yet in this election, tens of millions of Americans have supported a man utterly inexperienced in government office, who threatens to lock up his opponent if he wins and who to this day will not say if he will accept the outcome of the election.

More seriously, he has encouraged millions of devout followers to believe American democracy is rigged against them.

From Moscow to Beijing, despots, gangster governments and unelected elites have been rubbing their hands in glee.

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Whoever wins this election, it has been so bitterly divisive and uncivil it has already damaged America's image and its ability to project its values to allies and rivals around the world. And that has undermined its ability to maintain global stability.

It has been an unsettling year, with a second cold war with Russia looming, China expanding its military and territory, North Korea pursuing a nuclear bomb, the Middle East disintegrating further into violent chaos and a tide of humanity on the move.

That is the world Barack Obama bequeathes Hillary Clinton if she wins.

But on the campaign trail she has not proposed any major shift in foreign policy. She will need to establish herself as a statesman swiftly and decisively in such a volatile world.

But she will also need to heal division in this country and Americans' faith in themselves, if the world is to start believing in America again.

:: Watch every twist and turn of the US election results live on Sky News.

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