For much of the past three decades, nuclear weapons appeared to be a fading concern in international politics despite debates about the nuclear capacity of Russia, Iran and North Korea. Arms-control agreements and non-proliferation regimes such as the Treaty on the Non-Proliferation of Nuclear Weapons imposed limits on nuclear forces, as well as alliances reassured more vulnerable states and helped prevent the spread of nuclear weapons to many technologically capable countries.
Today, that era may be ending. The erosion of nuclear arms-control agreements such as NEW Start, intensifying rivalry between major powers, Russia’s aggression of Ukraine, and growing uncertainty about the durability of American security guarantees are reviving debates about nuclear deterrence among policymakers and leaders in Europe and Canada. Now, the war in Iran has further accelerated these discussions.
In Europe, policymakers are reconsidering how nuclear deterrence should function in a more unstable strategic environment. Even in Canada, a country that has long supported nuclear non-proliferation and avoided pursuing its own nuclear arsenal, the changing security landscape has prompted questions about the future of deterrence and alliance dependence. Are we on the brink of a nuclear proliferation?
Lesson of the Iran War
Although the Trump administration’s argument for launching a war against Iran keep changing, the military strikes highlight both the continuing relevance and the paradox of nuclear deterrence: states seek nuclear weapons primarily to prevent attacks, but military strikes against nuclear programs can also increase incentives for proliferation.
Iran has long pursued a nuclear enrichment program, especially after President Trump walked out of the 2015 nuclear deal in 2018, but it had not yet acquired nuclear weapons despite having the infrastructure and knowledge to do. In 2025, U.S. federal government analysts said Iran was years away from being able to produce long-range missiles.
The United States’ and Israel’s willingness to use military force against Iran in order to, supposedly, prevent Tehran from obtaining more nuclear capabilities could lead some to conclude that countries without nuclear weapons may be exposed to military pressure, while those that possess them enjoy a powerful deterrent against external intervention.
Could efforts to prevent nuclear proliferation, including military action against states suspected of pursuing nuclear weapons, inadvertently reinforce the perception that nuclear weapons are essential for security ? If political leaders conclude that nuclear deterrence is the only reliable protection against external intervention, the incentive to pursue nuclear capabilities could grow.
A More Fragile Nuclear Order
Renewed attention to nuclear deterrence is occurring at a moment when the global arms-control framework is weakening. For decades, non-proliferation treaties and agreements imposed limits on strategic nuclear arsenals and provided mechanisms for transparency and verification. The expiration of the New START treaty on 5 February 2026, the last major agreement limiting U.S. and Russian nuclear forces, marks the end of a system that had constrained the world’s two largest arsenals since the end of the Cold War.
Geopolitical competition between major powers is intensifying. Russia’s invasion of Ukraine has revived fears of large-scale conflict in Europe. Since the invasion of Ukraine in 2022, Russia has used nuclear rhetoric on several occasions to influence Western behavior and deter deeper involvement in the conflict.
China’s nuclear capabilities are less clear and transparent, though U.S. officials believe that China is rapidly expanding its nuclear arsenal. In an interview with the CBC, George Perkovich, Senior Fellow with the Carnegie Endowment for International Peace, said China is estimated to have around 600 warheads, still far below the U.S. and Russian levels, and that Beijing has traditionally maintained a “no first use” policy, meaning it pledges not to use nuclear weapons unless attacked first.
In the current geopolitical context, many U.S. allies are beginning to reconsider a question that once seemed settled: whether they can continue relying indefinitely on American nuclear protection.
The United States’ and Israel’s willingness to use military force against Iran in order to, supposedly, prevent Tehran from obtaining more nuclear capabilities could lead some to conclude that countries without nuclear weapons may be exposed to military pressure.
Europe’s Nuclear Question
Nowhere is this debate more visible than in Europe. For decades, the continent’s security architecture rested on a combination of NATO’s collective defense commitments and the extended nuclear deterrence provided by the U.S. That arrangement allowed most European states to avoid developing their own nuclear weapons.
Changing U.S. strategic priorities and its stated desire not to be “caretakers of west’s managed decline”, have also led several European policymakers and military officials in Finland, the UK, France, and Germany to question whether American nuclear protection will remain as dependable in the future as it was during the Cold War.
In a recent article in The Guardian, Richard Knighton, Chief of the Defence Staff of the United Kingdom, and German Army General Carsten Breuer called for deeper German-British collaboration to confront Russia’s military buildup. They argue that rearmament, including nuclear weapons, should not be seen as warmongering but as a responsible effort to deter aggression and preserve peace.
At the 2026 Munich Security Conference in February, European leaders, diplomats, and security officials debated how Europe should respond to a world in which U.S. dominance and leadership are no longer taken for granted. German Chancelor Friedrich Merz also stated that he had spoken with President Macron about European nuclear deterrence. In an interview with The Atlantic, Swedish Prime Minister, Ulf Kristersson, that he had had discussions about with France and the U.K.
One option proposed by European experts is expanding the role of the nuclear forces already possessed by France and the U.K., the only European countries with independent nuclear arsenals. France’s President Macron announced on March 2 that his country plans to increase its nuclear arsenal, currently estimated at about 290 warheads, marking the first expansion in decade. France and the U.K. have now deployed warships to the Mediterranean with the aim of protecting regional allies, defend military bases, and secure critical maritime trade routes.
Meanwhile, Finland’s recent consideration of lifting restrictions on hosting nuclear weapons illustrates how these debates are evolving in response to the changing security environment. While the change is meant to align Finland’s laws with its NATO membership, which it joined in 2023 after Russia’s invasion of Ukraine, it reflects growing security concerns about Russia. Finland wants to remove any legal barriers so that NATO could deploy or move nuclear weapons through Finland in a defense situation
These proposals do not necessarily signal an imminent wave of nuclear proliferation in Europe, but they indicate that nuclear deterrence is again being openly debated.
Canada’s Strategic Dilemma
Until recently, Canada had remained outside such discussions. The country has long supported the global non-proliferation regime and has chosen not to pursue nuclear weapons of its own. During the Cold War, Canada hosted American nuclear weapons as part of NATO’s deterrence strategy, but those weapons were removed by the mid-1980s. Since then, Canadian security policy has relied heavily on alliances, particularly its close relationship with the United States.
Yet the changing international environment has reopened the debate even in Canada. The current war in the Middle East, alongside growing tensions between the United States and Russia’s war against Ukraine, has raised questions about the stability of the international order, as Mark Carney made clear at Davos.
At the same time, some analysts and former military officials have begun to ask whether Canada should consider playing a more active role in nuclear deterrence within NATO.
Former Chief of the Defence Staff Wayne Eyre recently said Canada should not completely rule out the possibility of acquiring nuclear weapons in the future. Speaking in Ottawa, he argued that nuclear deterrence can provide greater strategic autonomy and suggested that reliance on allies, particularly the United States, limits Canada’s ability to act independently in security matters. Eyre emphasized that Canada should not pursue nuclear weapons now but said the country should keep the option open as the global security environment evolves.
His comments quickly drew political pushback from Canada’s Defence Minister, David McGuinty, who rejected the idea and reaffirmed Ottawa’s commitment to nuclear non-proliferation and the Nuclear Non-Proliferation Treaty.
At the moment, these discussions therefore remain limited but the fact that such questions are being raised at all reflects a deeper shift in the strategic environment.
For Canada, the practical challenges of developing a nuclear arsenal would also be immense. Producing nuclear weapons requires highly enriched uranium or plutonium, sophisticated delivery systems, and complex command-and-control structures. Pursuing such capabilities would require enormous financial resources.
Nuclear weapons would also do little to address the country’s most pressing security challenges, which include Arctic sovereignty, modernizing conventional forces, and strengthening continental defense.
Taking the pragmatic argument, Canadian experts such as Alexander Lanoszka and Janice Stein both argue that Canada have little reasons to develop a nuclear weapon. As Stein reflected on Peter Mansbridge’s podcast, in what scenarios would Canada even use it? If the U.S. ran a disinformation campaign in Alberta? If the U.S. sailed a warship through the north-west passage? If the U.S. invaded Canada? There are no conceivable scenarios that demand the acquisition of expensive nuclear weapons.
A Dangerous Moment for Nuclear Policy
The renewed debate about nuclear weapons says a lot about the changing nature of the global security order. As the Munich Security Report 2026, aptly titled “Under Destruction”, remarks, nuclear deterrence debates are returning because alliances are less predictable. For decades, the international nuclear system rested on three pillars: arms-control agreements that limited nuclear arsenals, strong alliances that reassured vulnerable states, and a widely shared norm against nuclear proliferation.
Today, these pillars are under strain. Nuclear weapons can deter large-scale war between major powers, but they can also encourage other states to seek the same protection. If more countries conclude that nuclear weapons are the ultimate guarantee of security, the risk of proliferation could increase dramatically.
The question facing countries like Canada is therefore not simply whether they should consider acquiring nuclear weapons but whether the international community can preserve a system that discourages their spread. If that system weakens, the return of nuclear competition may become a new defining challenge.