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It’s probably just as well that the Doomsday Clock is only changed once a year. The clock, which measures existential risks to humankind, was moved forward by one second at the end of 2024 to 59 seconds to midnight. This was in large part because of the war in Ukraine and the very real risk that it might bring a confrontation between the US and Russia which could turn nuclear.

As things stand you would get fairly short odds on the second hand nudging even closer to midnight at the end of 2025. And what would probably prompt a hollow laugh from the scientists that decide where the hands should point is that the latest crisis appears to be the result of some characteristically wayward talk from the US president, Donald Trump.

Flying home from South Korea after his summit with Xi Jinping on the sidelines of the Apec conference on October 30, Trump announced that “because of other countries’ testing programs”, he had ordered the Pentagon to restart the process for testing nuclear weapons “on an equal basis. That process will begin immediately.”

His statement followed an announcement by the Russian president, Vladimir Putin, about recent tests of a new nuclear-powered cruise missile, the Burevestnik. Days later, Putin announced that Russia had tested a nuclear powered drone torpedo called Poseidon.

Potent weapons both, no doubt. And both capable of carrying nuclear payloads. But neither are nuclear weapons in themselves. Russia has not carried out nuclear tests since the end of the cold war and nor has China, the third largest nuclear power after Russia and the US.

So now Putin has responded by announcing Russia will also resume testing, citing Trump’s statement and the ongoing modernisation of America’s nuclear forces. But at the same time, Russian diplomats are talking with their US counterparts to clarify Trump’s intention, reporting that the White House and the State Department “evaded a specific response”.

It’s a reminder from the cold war of just how delicate the balance can be with two leaders at loggerheads who control the means to destroy the planet several times over.

Tom Vaughan, a lecturer in international security at the University of Leeds, notes that the UK is pressing ahead with its procurement of F-35 stealth fighter aircraft. These can carry nuclear bombs but, as Vaughan notes, would require US authorisation before they could be used. Equally, Britain’s nominally independent nuclear weapons system, Trident, is reliant on US support and maintenance.

As Vaughan points out, it makes the UK into “a target in any nuclear war that might be started by two unpredictable and violent superpowers”.

For anyone who grew up in the 1970s and 1980s, these are familiar themes. But we heaved a sigh of relief when, thanks to leaders such as Ronald Reagan and Mikhail Gorbachev, it felt as if we were stepping back from the brink of an unthinkable conflagration. And when the fall of the Berlin Wall was followed by the end of the cold war, it felt as if those days might be gone for good.

Read more: Talk of new atomic tests by Trump and Putin should make UK rethink its role as a nuclear silo for the US

Nor has the rapidly increasing diplomatic temperature escaped Hollywood film-maker Kathryn Bigelow. Bigelow, whose successes include The Hurt Locker and Zero Dark Thirty, has a new film streaming on Netflix which addresses this theme. A House of Dynamite imagines how officials in the US might respond if it looked like a nuclear strike was imminent.

Mark Lacy, a philosopher at the University of Essex, who has written for us several times about the future of war, says the film paints an imaginative picture of the confusion and complexity of such a situation, in which it’s more than likely that an enemy which is capable of disrupting communications – something we are already seeing in the forms of repeated cyberattacks by inimical state-sponsored enemies.

To paraphrase Lacy’s conclusion, it’s just as well this is fiction. But Trump and Putin’s latest exchanges have made it just that little bit more easy to imagine things getting out of hand.

Read more: Netflix's A House of Dynamite sounds the nuclear alarm, but how worried should we be?

Mamdani: a politician who listens

The other big US news this week was from Big Apple, where democratic socialist Zohran Mamdani won the New York City mayoral election. He was up against Andrew Cuomo, the former Democrat governor of New York state who won 41.6% of the vote, and Republican Curtis Sliwa, who won just 7%.

Mamdani is the first Muslim mayor of New York city, the youngest since 1892 and the first mayor born in Africa. He won on a platform of lowering the cost of living, introducing rent controls and providing free buses and childcare for all. To do this, he proposes taxing millionaires more.

Predictably Trump, who has launched regular attacks on Mamdani in recent months, calls him a communist and has said he will defund New York (something he doesn’t have the constitutional power to do – not that this would stop him trying, of course). Israeli prime minister Benjamin Netanyahu has called him a “mouthpiece for Hamas propaganda”. Which is all very predictable.

But most New Yorkers weren’t in the mood to listen to either criticism. Which is apt, as one of the refreshing features about Mamdani’s style of politics is his ability to listen to others, says Daniel Hutton Ferris, a lecturer in political theory at Newcastle University.

Hutton points to Mamdani’s habit on the campaign trail of soliciting people’s views, especially those of people who weren’t intending to vote for him. He says this is a smart tactic, not only because people like to be heard and respect politicians who listen, but also because of the voting system in New York.

Similar to the single transferable vote system used for Australia’s federal elections, New York’s voting system asks voters to rank candidates in order of their preference rather than choosing just one. That way they can put the candidate who they dislike most at the bottom of the list. If their candidate doesn’t win, the vote goes to the person next on the list of a voter’s preferences.

As Hutton says, it’s a great way of dealing with polarising candidates. It penalises people who rely on taking extreme and divisive positions to attract the support of a core base of passionate supporters. The UK spurned a chance to switch to something like this in the 2011 referendum.

Read more: How Zohran Mamdani's 'talent for listening' spurred him to victory in the New York mayoral election

Mamdani wasn’t the only winner on Tuesday. The Democratic party scored victory in two gubernatorial elections and successfully passed proposition 50 in California, which allows for the “redistricting” of voting areas. It’s a move that could provide the party with as many as five seats in next year’s midterm elections.

It’s a sign, says Andrew Gawthorpe, an expert in US politics at Leiden University, that the coalition that delivered Trump to the White House in 2024 might be beginning to collapse. Close analysis of the voting patterns shows that groups like Latino voters, who came out in unexpectedly high numbers for Trump in the 2024 election, may be moving back to the Democrats. Equally, many suburban areas of Virginia and New Jersey, which turned out for Trump in 2024, voted heavily for the Democrat candidates.

It’s premature to predict the outcome of next year’s elections based on Tuesday night’s results, cautions Gawthorpe. But it’s certainly a sign that the self-styled “highest polling Republican President in HISTORY!” may not be as popular as he likes to tell himself.

Read more: US election results suggest Trump's coalition of voters is collapsing

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