On 5 November, people around the globe will tune in to watch the world election. It’s not a “world” election in the sense of the World Cup – a football championship in which many nations actively participate – but it’s much more than a World Series, the curiously named baseball championship that involves only teams from North America. This year has been called the biggest election year in history. By the end of it, something approaching half the world’s adult population will have had the possibility to put a cross against a name on a ballot paper. But the US presidential election is the year’s big match.

Why? Because this is a genuine democratic election that will result in a single person holding exceptionally concentrated executive power in what is still the world’s most powerful country. It’s a highly watchable soap opera, with a classic plot familiar to all. And one of this year’s two contenders, Donald Trump, is a danger to his own country and the world. If the “election” of the president of China, the world’s other superpower, were a genuine democratic choice, that event would perhaps be as consequential. But it isn’t, so it isn’t. Russia had a presidential “election” earlier this year, but at issue was only the size of Vladimir Putin’s declared majority.

Equally, if the US were a parliamentary democracy, and especially if it had an electoral system of proportional representation, the stakes would not be so high. The resulting government would depend on the party-political composition of parliament and in many such countries you routinely end up with coalition governments. Even in Britain’s “elective dictatorship”, as the Conservative politician Lord Hailsham (Quintin Hogg) once characterised the British political system, the prime minister has significantly less power than a US president. President Emmanuel Macron of France is now behaving as if he thinks he is the US president, with an unrestricted right to form the nation’s government, but that’s not what his country’s constitution says.

As the American political scientist Corey Brettschneider reminds us in his new book, The Presidents and the People, the danger inherent in this concentration of power was already highlighted by Patrick Henry, a hero of the American war of independence, when the US constitution was debated at the Virginia ratifying convention in 1788. What if a criminal were elected president, Henry asked. What if he could abuse his position as singular head of the executive branch and commander in chief of the military to realise his criminal ambitions? Well, here we are 236 years later, and a convicted felon and notorious fan of autocrats is neck-and-neck with the newly crowned Democratic candidate, Kamala Harris.

If her opponent were Nikki Haley, the runner-up in the Republican primary contest, the drama would be nothing like as intense. This would be something like a normal election. But it’s Trump, so it isn’t.

I arrived in the US the day before Joe Biden finally conceded that he would not stand again. Since then we have witnessed a tidal wave of hope flow into the candidacy of Harris and her folksy running mate, Tim Walz. This culminated in the Democratic national convention in Chicago, where the usual orgy of razzmatazz was accompanied by genuine joy and unabashed flag-waving patriotism.

To their own and everyone else’s surprise, the Democrats give every impression of being united. Harris raised about $500m for her campaign in just a month. She is not a great orator, like Bill Clinton and both Obamas, but she gave an excellent acceptance speech. She introduced herself to the American public as the child of an indomitable Indian immigrant mother. She elaborated on her campaign’s brilliantly chosen theme of freedom – therefore taking what has been for years a Republican leitmotif and reconnecting liberty with liberalism. She listed some of those freedoms from that are also freedoms to: women’s freedom to decide about their own bodies, the freedom to live safe from gun violence, the freedom to love whom you choose, the freedom to breathe clean air, the freedom to vote.

Importantly for a female candidate with a left-liberal background, Harris successfully conveyed the image of a strong leader who would give the US “the strongest, most lethal fighting force in the world” and enable it to out-do China in the competition for the 21st century and “stand strong with Ukraine and our Nato allies”. In substance, 90% of this could equally have been said by Biden, but the way she said it – not least in seeming credibly to care about the heartbreaking scale of Palestinian suffering – made it feel new and promising.

As a result, enthusiasm for the Democratic candidate has soared – but only to the point where this election has become too close to call. Recalling his own electrifying slogan from the 2008 election, “Yes we can”, Barack Obama told the convention, “Yes she can!”

Yes, she can; but that doesn’t mean she will. She may be marginally ahead in nationwide polling, but with the antiquated electoral system that the US uses for its presidential election, she could win the popular vote, as Hillary Clinton did in 2016, and still lose because of a few tens of thousands of swing voters in battleground states in the midwest and the sun belt.

One leading pollster tells me that the top three issues for the electorate are the economy, crime and immigration, and on all three, Republicans typically have the edge. Trump himself looks all over the place, giving long rambling speeches, but he’s a formidable political counter-puncher.

The social aquifers of white working-class anger are still very full, especially among men. (The gender gap is very marked in the Harris v Trump contest.) Moreover, if it’s a narrow victory for Harris, Trump will immediately declare the election “stolen”, and we will be set for a long bout of bitter litigation, as happened in 2000, but with the supreme court now seen by many as biased towards the Republican side.

All of which is a long way of saying: nobody knows. And that, after all, is the hallmark of a genuine democratic election. But here’s the uniquely curious thing about this one. Millions of people all over the world, from Austria to Zimbabwe, not only follow it closely but also know many of the sometimes arcane psephological details that may decide the result in the electoral college. This is not just because Washington is the world’s political theatre, as much as Netflix is now the world’s movie theatre, but because the result will have important consequences for them. If you are Ukrainian or Palestinian, it may literally be a matter of life and death.

Ultimately, what is most peculiar about this world election is the sheer incongruity of cause and potential effect. Whether women and children in Kharkiv or Rafah live or die may depend on what Mike the mechanic in Michigan and Penny the teacher in Pennsylvania think about their grocery bills.