You know there’s a problem when Poland asks in on the nuclear club

This, let me suggest, is the imperceptible forcefield around the Pax Americana. Nato was not about words on paper so much as the faith felt by partners in the security guarantees, which deterred aggressors too. Similarly, open trade was not about legal frameworks but the collective sense of predictability in action and consequence that has been slowly building through the centuries since Magna Carta — and which America formalised in the postwar institutions.

• Betrayed by ‘blowhard’ Trump? Ally with us instead, says China

But this sense of trust has been — how can I put it? — obliterated. Nobody in Europe, Japan, South Korea or beyond any longer believes America’s word. It is why the question of security guarantees for Ukraine is, in a sense, beside the point. Who trusts that Trump would honour any commitment, given that he has a track record as long as your arm of breaching contracts in private business? How could America itself be trusted when it has put its faith in this charlatan for a second time, and in his smirking sidekick, JD Vance?

Who — on the wider point — can trust the terms of any trade deal, for instance the one the White House is dangling before Sir Keir Starmer, given that it’s all too obvious that he hopes to peel the UK away from Europe and then shaft us at our moment of maximum vulnerability? What Nato member trusts the Article 5 guarantee, given that Trump struggled not to laugh when asked if the US would come to the defence of the Baltics? I think we can all see a future in which Trump argues that an assault on, say, Latvia is nothing of the kind. Latvia is the aggressor, he will say, and Russia the victim, and what about the juicy minerals that might be carved up between us, Vlad?

Trust, the most subtle and beautiful of all social phenomena, and also the most important, has vanished in a puff of Trumpian smoke. And the most momentous consequence — and the one few wish to discuss — is that every mildly advanced nation is now seeking nuclear weapons of its own. After all, if you can’t trust your partner any more — indeed, if that partner is now a bully willing to threaten your territory, as with Canada and Denmark — isn’t that a logical response?

• Poland plans to give all men military training in ‘race for security’

In a speech to the Polish parliament on Friday, Donald Tusk called for rearmament of a stunning kind. “We must be aware that Poland must reach for the most modern capabilities also related to nuclear weapons and modern unconventional weapons,” he said — while calling for a huge increase in conventional forces. Germany, Japan and Saudi Arabia are considering nukes, as is South Korea (a recent poll showed a majority of the public in favour). And who can blame them when you consider the price Ukraine is paying for surrendering its warheads after the fall of the Berlin Wall, its heroic leader mocked in the Oval Office, his nation suffering agonies while the US (a signatory to the Budapest memorandum, let us not forget) gloats over the withdrawal of its intelligence umbrella?

Please be in no doubt of the danger of this shift. Experts say that even a war between, say, India and Pakistan (with only a handful of warheads between them) would unleash a nuclear winter that would kill billions with its devastating effect on crops and climate. Sharon Squassoni of George Washington University, who once served in the US government, told Newsweek (with impressive understatement) that we are on the verge of “the worst chain of nuclear weapons proliferation since the 1940s”, which would “make the world a much more dangerous place”.

Yet I doubt the White House has any idea of what is being unleashed. I listen in wonder as Vance proclaims that America should “stand alone”. Does he not grasp the intricacy of the global supply chains without which the phone on which he types misinformation would be impossible, or the interdependencies upon which we all rely, from communications protocols to aviation safety standards — as well as norms on IP and copyright, serially violated by China and Russia, with which Trump appears to wish to do business? Does he not realise that it is not just nuclear proliferation that hovers like an apparition — raised by this fracturing of the shared system of deterrence — but a splintering of the broader co-operation with allies on which America utterly and inexorably relies?
We should certainly acknowledge that Europe is partly responsible for the vista that now confronts us.

• Trump: Putin does ‘what anybody else would do’ in Ukraine

It was our reprehensible freeloading on American defence spending that helped to fuel Trump’s rise to power — and I will never tire of repeating this truth. But I hope most people can see that the Trumpian backlash has gone beyond proportionality or reason. As with any cult, fidelity to the Maga cause is demonstrated by how much one is willing to abase oneself before the messiah, hence the spectacle of Republicans cheering ever more loudly as Trump filled the air with bare-faced lies in his speech to Congress last week.

But perhaps there’s a glimmer of hope. There was a moment during the speech when the camera panned to the assembled audience. Well over half of the Republicans were cheering like crazy: true cultists. Yet I couldn’t help noticing the curious expression on some of the others. Their grins were rictus-like, unnatural: they looked not dissimilar to hostages smiling to camera in those strange, forced videos. I inferred that at least some of them realise the danger posed by Trump and his fellow arsonists. They smile and applaud despite themselves.

This should encourage us that a pushback is possible. I know that this may sound unrealistic when Trump has captured the party, hook, line and sinker — but look again. Cracks are appearing. Canada is defying the threats and Trump has blinked. Europeans are mustering resolve. Stock markets are turning. Inflation expectations are rising. Internal squabbles are breaking out. Is it too much to hope sane Republicans might find their backbone and start to resist?

You may say it’s a forlorn hope, an unrealistic hope, but let me say this: it is the only hope. We rightly worry about Iran developing nuclear weapons, but a more generalised proliferation, with ever more fingers on the hair-trigger of mutual annihilation, would be catastrophic. This is a difficult truth, but I hope a clarifying one. It is arguably not too late to pull back from the brink.