US nuclear umbrella will no longer shelter us from the rising threat of war

Germany has joined the growing group of US allies realising that they can no longer trust the American nuclear umbrella to protect them. Because Donald Trump is now holding it. So Chancellor Friedrich Merz last week asked France’s Emmanuel Macron about taking shelter under the French nuclear umbrella instead.

The French never trusted that America would protect an ally from nuclear attack if it meant risking an attack on the US itself. As French president Charles de Gaulle famously challenged John F. Kennedy in 1961: “Would the US really be willing to ‘trade New York for Paris’?” In other words, if France were at risk of atomic attack from Moscow, would an American president sincerely threaten – or even strike – Moscow to protect it? The French have kept their own nukes to this day.

Most other US allies, including Australia, accepted the American guarantee, with the notable exception of Britain, which has retained its own nuclear capability.

It’s now clearer than ever that de Gaulle was right. Peace-loving people prefer not to think about nuclear weapons. Ever. Responsible leaders of peace-loving peoples must think about it. Now.

The US guarantee is now a fiction. Can anyone imagine Donald “America First” Trump actually threatening Moscow or Beijing or Pyongyang with nuclear attack in order to protect Melbourne, Berlin or Paris?

The Trump administration’s officials can’t. Trump’s head of defence policy, Elbridge Colby, has said so: “It’s obviously not going to happen,” he told me in July 2024, before Trump won his second term as president. Colby today is the undersecretary of defence for policy in Trump’s Department of War.

“I don’t think there’s any way that the American president would actually risk losing, like, five American cities, because of something that North Korea did, because the stakes are too low for Americans,” Colby said in an interview.

He drove the point home: “You know, there are no fallout shelters in Seattle, there are no civil defence drills. Right? If we actually were preparing to potentially lose a city because of something, you would see that evidence. And so it’s obviously not going to happen.”

Does his view still hold now that he’s in government? He is principal author of the 2026 US National Defence Strategy published last month. Unlike previous such US defence manifestos, it does not explicitly mention the nuclear umbrella at all, which is formally known as “extended deterrence”. Instead, it states that America’s allies would “take primary responsibility” for their own defence.

One by one, bit by bit, governments are starting to confront this reality. Among US NATO allies, Germany now joins Poland and Sweden in breaking the long-standing taboo and daring to speak the “n” word, considering their options.

In the Indo-Pacific, US allies South Korea and Japan are debating the nuclear option too. Three-quarters of South Koreans want their country to forget the US umbrella and arm itself with nukes.

Most shocking is Japan, the only nation ever to endure nuclear attack. Prime Minister Sanae Takaichi has refused to confirm to a parliamentary committee that her government would remain committed to its non-nuclear principles. Her party’s policy chief later confirmed that a formal review was under way: “It’s our responsibility as the ruling party to hold talks without any sacred cows.”

What about Australia? When China detonated its first nuclear test in 1964, Canberra looked at its nuclear options, including buying nuclear arms from Britain. Liberal John Gorton, prime minister from 1968 to 1971, wanted Australia to develop its own nuclear deterrent. He didn’t trust the US or Britain.

Gorton put his own twist on de Gaulle’s proposition: Would Americans be willing to trade San Francisco for Sydney? He thought the answer self-evident – no.

He approved construction of a nuclear reactor at Jervis Bay in NSW to supply fuel. Its footings in the bush remain to this day, literally a concrete reminder of his intentions.

But when Gorton lost power, Australia lost interest and settled snugly under the American nuclear umbrella. “For too long we have avoided thinking seriously about nuclear weapons,” says Professor Brendan Taylor, head of the Strategic and Defence Studies Centre at ANU. “That is no longer sustainable,” he wrote in the journal Australian Foreign Affairs. “Australia has never confronted a challenge like the new nuclear age now unfolding in Asia.”

How so? It’s not just that the American umbrella is in tatters. It’s also that the risks have risen. Vladimir Putin has threatened to use tactical nukes against Ukraine. The last remaining nuclear arms limitation treaty between the US and Russia expired two weeks ago.

Most importantly, Xi Jinping has launched explosive growth in the size and capacity of China’s nuclear forces. It already has missiles capable of carrying nuclear warheads as far as Australia. Beijing refuses to disclose its intentions or negotiate its deployments.

Xi already has used economic coercion against Australia. By sending a naval task group for the first time to circumnavigate Australia and conduct live-fire exercises off Sydney last year, he was signalling that China has the reach to use military coercion against Australia too.

There’s a common misunderstanding that a country needs nukes only if it intends a nuclear war. This is wrong. They’re also essential for waging conventional war against a nuclear-armed enemy.

By way of illustration: If one of China’s dangerous intercepts of an Australian navy or air force asset should turn deadly, and incident escalates to skirmish and skirmish to fight, Australia would be forced to the negotiating table first. Why? Because no matter how successful Australia’s forces, China can always escalate to the level of nuclear threat. We cannot. Unless the US backs us, which, as Colby attests, it won’t.

In other words, a country at risk needs the deterrent power of nuclear arms even if it has no intention of launching a nuclear war. The AUKUS submarines are to be nuclear-powered, not nuclear-armed.

The head of the ANU’s National Security College, Rory Medcalf, says that Australia needs to beware “a cascade of proliferation”, not by enemies but by friends.

“If Japan and South Korea decided to develop nuclear capability, that would be the signal to Australia to think anew about this. If one did, the other would. It would signal a lack of confidence in the US umbrella. That would be a different world to think about. We’re still a long way from that point, but it would put us in a different world.”

Peter Hartcher is the international editor for the Herald and The Age.

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