AS Trump brutally hammers out a settlement for Ukraine and Russia, he’s also been hammering Europe for vast, cold-war levels of military spending. And European leaders seem very keen to oblige.

Along with Keir Starmer’s so-called peace plan for a 30,000-strong European army, France’s Emmanuel Macron and Germany’s chancellor-in-waiting Friedrich Merz are pushing for a European “nuclear umbrella” — where France could deploy its nuclear-capable jets outside its borders. Merz also wants Britain to step up and deploy its British nuclear submarines to “defend” Europe against Russian aggression.

So what does this “nuclear umbrella” really mean in practice — and what are the risks?

Currently, France has 290 warheads that can be launched by nuclear-capable fighter jets and nuclear-powered submarines. While France’s nuclear weapons doctrine states the weapons are to “defend” its “vital interests,” in 2020, Macron announced that France’s “vital interests now have a European dimension.”

However, he also stated in 2022 that France’s vital interests “would not be at stake if there was a nuclear ballistic attack in Ukraine or in the region.” So, Macron would have to radically shift French nuclear doctrine if the “defence” of Ukraine was to be incorporated. It would mean France being prepared to launch a nuclear strike on Russia, a country that currently possesses over 5,000 nuclear weapons.

Speculation about how this nuclear umbrella would work includes the possibility of nuclear-armed jets being stationed in Germany or Poland (both countries have expressed interest).

Stationing nuclear weapons in countries that don’t have them — known as nuclear sharing — is in violation of the Nuclear Non-Proliferation Treaty. If a nuclear-sharing agreement was secured between France and Poland, nuclear-armed jets could be deployed along Poland’s 130-mile border with Russia.

If a future ceasefire arrangement was breached, could French nuclear jets deployed in Germany and Poland be used against Russia?

Another suggestion is that these French bombers could patrol European borders. Would such borders also include Ukraine’s? In the event of a ceasefire breach, would nuclear-armed French bombers also be deployed in Ukraine?

While Macron’s “nuclear umbrella” idea is getting widespread coverage, these terrifying scenarios — and the human cost of such confrontations — are not.

Behind these wild proposals is the speculation that the US under Trump will withdraw its military and nuclear presence in Europe — and turn off the nuclear tap for its “critical” partner, Britain.

In Britain, figures like former defence secretary Malcolm Rifkind are arguing that Britain has to work more closely with France in case “US reliability ever came into question” in “defending Europe against Russian aggression.”

It has also prompted more challenges to Britain’s so-called special relationship with the US. And shone a welcome spotlight on Britain’s nuclear dependence, with widespread reporting that the ballistic missiles launched from Britain’s nuclear submarines are leased from the US, and that the warheads are a US design.

In fact, the whole nuclear weapons system is under US-led Nato command. So, if Britain wanted its nuclear-armed submarines to be part of a European nuclear umbrella, it would effectively have to get permission from US President Donald Trump.

In response, military analysts like Marion Messmer argue that to end its nuclear dependence on the US, Britain should build an entirely new, air-launching nuclear weapons system. Paid for, no doubt, by British and French taxpayers.

This would be on top of the £205 billion the British government is already wasting on the system’s replacement. A programme the government’s own watchdog has labelled as “unachievable” and unaffordable.

Prime Minister Keir Starmer is silent on the European nuclear umbrella. Having positioned himself against Trump, as champion of Ukraine’s Nato membership, he shifted rapidly to parroting Trump’s “peace through strength” rhetoric.

He now argues that his “peace plan” should be made “in conjunction with the US” because “it’s that ability to work with the US and our European partners that has kept the peace for 80 years now.”

Such an alliance has, of course, totally failed to keep peace, and instead has driven war and poverty globally, causing humanitarian catastrophe, economic crises and environmental devastation.

Instead, political leaders need to get a grip on reality. Bankrupting Britain and Europe in some desperate attempt to replace the US’s $800 billion military spending in Nato will destroy our societies and worsen all these global crises.

Sustainable peace for Europe, Ukraine and Russia cannot be achieved by troops and missiles, backed by the constant, looming threat of nuclear war. That means developing a sustainable security architecture that can ensure long-term peace and prosperity for the entire region.

It means withdrawing US nukes from Europe and Russian ones from Belarus. And it means the US, Russia, Britain and France developing programmes to get rid of their own nuclear weapons. As Trump has said he wants nuclear disarmament, Starmer should be working with him to do so.

Sophie Bolt is general secretary of the Campaign for Nuclear Disarmament.