A Hobbesian World: The Trump administration has threatened the uncontrolled collapse of the nuclear non-proliferation regime

A shot in the foot

With the arrival of Donald Trump, the issue of nuclear weapons spreading beyond the small group of nuclear powers has taken on a fundamentally new dimension. ‘Get ready for a new nuclear age’ is the title of an article by political scientist Gideon Rose in Foreign Affairs. Indeed, on the one hand, Trump is issuing a tough ultimatum to Iran, demanding that it agree to a deal that would require abandoning nuclear weapons development. On the other hand, Trump's revolutionary willingness to reconsider past alliance commitments in both Europe and the Pacific – and to pressure allies by threatening to abandon these commitments – undermines the alliance system that has shaped the global order since World War II. A key component of that order, in turn, has been the nuclear nonproliferation regime.

Previously, the desire to obtain nuclear weapons was mainly expressed by rogue states like North Korea or Iran. But today, this idea is increasingly taking hold among 'First World' countries alarmed by Trump's erratic behavior and that of his administration, note international relations experts Debak Das and Michelle Epstein in an article published in Foreign Policy. Can US allies trust that the Trump administration would support them in the event of a nuclear threat from Russia, China, or North Korea? This question is now being asked by Germany, Poland, Japan, Taiwan, and South Korea. And if one of the US's European or East Asian allies decides to secure itself with its own nuclear arsenal, this could trigger a domino effect, the authors suggest.

At the same time, a wave of nuclear proliferation among Washington's partners would directly harm US national interests as currently defined, according to a commentary in the War on the Rocks portal. Trump's ‘America First’ doctrine relies on the primacy of American power. However, if new nuclear powers emerge among US partners, this weakens American dominance, increases allied independence from Washington, and deprives the US of a key lever of influence over its partners. In other words, nuclear proliferation – whether among US allies or adversaries – undermines the power privileges Washington enjoys today.

The situation appears truly paradoxical. While Trump's inconsistent rhetoric forces allies to consider even the most catastrophic scenarios, US and NATO policy on nuclear weapons is moving in the opposite direction. NATO's nuclear deterrent capability in Europe is actually being strengthened, as noted in a review by German research centre DGAP. B61 nuclear warheads stored in Germany, Belgium, Italy, and the Netherlands are being replaced with the new, modernised B61-12 version. Additionally, all these countries have purchased US F-35 fighter jets as part of their nuclear delivery systems. Next year, Germany will receive the first of 35 F-35 fighter-bombers, and US arms depots in Europe – including the Büchel base in Germany, where American nuclear bombs are stored – are currently being upgraded to accommodate new types of weaponry. Furthermore, the US is preparing to deploy B61-12 bombs in the United Kingdom, where American nuclear weapons have not been stationed since 2008.

However, all of this seems futile for Europe in the absence of the most crucial element of collective deterrence – trust in Washington’s political decisions and strategic direction.

The non-proliferation regime: Locke's world versus Hobbes' world

To be fair, the erosion of the nuclear nonproliferation regime is not solely Trump's doing. The very existence of such a regime is an unusual episode in human history. In a way, it represents a relatively successful attempt to build a world based on John Locke’s vision of a functional social contract within the traditionally Hobbesian ‘war of all against all’, observes Gideon Rose. When nuclear weapons first appeared in the hands of the US and the USSR, and later in those of the UK and France, it seemed obvious that other countries would seek to acquire them as well – just as has always happened when significant military innovations emerge.

However, the US-led collective security coalitions provided an effective alternative to this scenario. Moreover, the US's unique position – backed by the combined strength of its allies – significantly reduced the risk of even non-allied nations falling prey to the ‘rule of the strong’. This diminished their incentive to acquire the ultimate deterrent weapon. For example, the international coalition led by the US restored Kuwait's independence after Iraq's attempted occupation in 1990.

Although in two conflicts – the Arab-Israeli and Indo-Pakistani wars – the United States failed to fulfill its role as an external guarantor, these cases were considered exceptions and did not undermine the Nuclear Non-Proliferation Treaty (NPT), signed by the initiating countries in 1968 (later joined by 190 states).

However, an opportunistic trend has always existed in this history, Rose reminds us. For instance, the United Kingdom continued its own nuclear programme after the US halted cooperation with London under the Manhattan Project, successfully testing its nuclear bomb in 1952. The next sceptic was French President Charles de Gaulle: just as Britain did not entrust its fate in this matter to the US, de Gaulle chose not to rely on America's and Britain's collective guarantees. As a result, France developed its own bomb by 1960 and later assisted Israel in its nuclear weapons programme. Finally, after the Cold War ended, in 1993, American political scientist John Mearsheimer argued in Foreign Affairs – contrary to the consensus of the Clinton administration and the US foreign policy establishment – that their push for Ukraine's denuclearisation was a grave mistake that would leave Ukraine defenceless against future Russian revanchism.

All sceptics proceeded from the idea that in the face of a real nuclear conflict, the willingness to intervene for the sake of another country could be significantly lower than what is declared when the threat remains largely theoretical.

In the early 21st century, the nonproliferation regime suffered several major blows. First, for more than 20 years, the US, Israel, and European countries have failed to stop Iran’s nuclear programme, which itself is a critical indicator of the regime's vulnerability. In the 2010s, during Trump's first presidency, the US suffered a complete failure in preventing North Korea’s nuclearisation. In 2014 and again after 2022, the Western coalition was unable to stop Moscow’s aggression against Ukraine. The security guarantees provided to Ukraine by the US and the UK under the Budapest Memorandum, in exchange for Kyiv surrendering the Soviet nuclear arsenal, turned out to be worthless. In the US, officials now prefer not to mention them at all. Finally, after the full-scale invasion began, Vladimir Putin successfully used nuclear blackmail to limit the scale of Western military aid to Ukraine.

Even without Trump, trust in the nonproliferation regime had already been undermined. The trajectory of negotiations on North Korea’s nuclear programme clearly indicated that deterrence sceptics were, in many ways, correct.

The world's nuclear arsenal in 2024

Pan-European deterrence and the domino principle

The new US administration has demonstratively abandoned the role the United States has played in global politics for the past 80 years and the commitments that came with it. This is leading to a fundamental shift in perceptions not only at the governmental level but also in public opinion across many countries.

According to a poll conducted in South Korea in early 2024 (notably, before Trump’s second return to the White House), 61% of respondents said they did not believe the United States would use its nuclear deterrence in the event of a crisis on the Korean Peninsula if it risked an attack on the US itself. Consequently, 73% supported the idea of their country developing its own nuclear weapons. A February 2025 survey found that 52% of Poles wanted their country to possess nuclear weapons, while 28% were opposed (UCE Research poll, CAWI method – web interviews). Among supporters of the Confederation, Law and Justice, and Third Way parties, 60–70% backed the idea.

In Germany, a February 2025 survey showed that 64% opposed their country acquiring nuclear weapons, while 31% supported it – an increase of four percentage points from the previous year. However, it is important to consider that before Russia launched its war against Ukraine, Germany was staunchly anti-nuclear. Most Germans supported removing even American nuclear weapons from their country and favored joining the Treaty on the Prohibition of Nuclear Weapons. As recently as 2020, only 40% of Germans believed that US nuclear weapons stationed in Germany contributed to deterrence. By 2022, that figure had risen to over 60%, according to polls.

Immediately after winning the election, doubting NATO’s ability to survive in its current form, Germany’s new Chancellor Friedrich Merz called for negotiations with Paris and London on expanding their nuclear ‘umbrella’. The UK immediately agreed to begin a ‘strategic dialogue on protecting our allies on the European continent through... [nuclear] deterrence’. For France, which has always advocated for Europe’s 'strategic self-determination' and distancing itself from the US, this was seen as a victory for French political thinking (→ Re:Russia: Europe's Strategic Autonomy).

However, British and French nuclear stockpiles have always been merely a modest supplement to the US arsenal, notes Robert McKinnon in his review for GMF. TThe British deterrent relies solely on submarines and uses American Trident missiles for delivery, making it significantly dependent on the US (though some experts dispute this view and argue that the UK retains medium-term independence in deploying its nuclear forces). France, by contrast, has full nuclear independence, but its arsenal is designed to meet sovereign national needs rather than to protect all of Europe. Thus, if Europe chooses to shift toward a Franco-British deterrence system, both countries will need to expand and adapt their nuclear capabilities.

Still, the creation of a European nuclear shield may not be the only response. Domestic political disagreements within European nuclear states could also play a role, note the authors of an article in Foreign Policy. For instance, Marine Le Pen recently stated that France should not share its nuclear weapons, 'let alone delegate' their use to other European countries. Against this backdrop, other European states may conclude that relying entirely on France’s nuclear umbrella is risky, given the nonzero possibility of right-wing forces coming to power in France. In the past, London did not trust Washington, and Paris did not trust Washington or London. So why should other countries fully trust London and Paris now? Rose poses this question. It is no coincidence that, while supporting the idea of expanding France’s nuclear umbrella, Polish Prime Minister Donald Tusk bluntly remarked that Poland would be safer if it had its own nuclear arsenal.

With the logic of collective deterrence being called into question, the logic of nonproliferation sceptics is pushing national governments to take the next step along the path previously followed by post-war Britain and France. Even if collective deterrence guarantees exist, it still makes sense to possess at least a small national nuclear arsenal to avoid being left helpless should those guarantees be questioned, ignored, or outright forgotten – just as happened with Ukraine.

A dangerous path to a new equilibrium

Today, South Korea, Japan, Iran, and Saudi Arabia are considered so-called latent nuclear states – countries capable of developing their own nuclear weapons very quickly. The same applies to several European nations, including Germany, Belgium, Italy, Spain, and the Netherlands. However, the case of North Korea, a country that is economically and technologically underdeveloped and subject to strict international sanctions, demonstrates that developing a nuclear bomb is not particularly difficult for a much larger number of countries. Some states may even have emergency programmes or preliminary capabilities in place to advance down this path. For example, Sweden pursued an independent nuclear programme until the 1970s, as Gideon Rose reminds us. The circle of nations capable of rapidly acquiring nuclear weapons could be much wider than currently assumed.

Experts believe that South Korea is the most likely candidate to become the next nuclear power. Japan is so advanced in nuclear technology that developing nuclear weapons would be a straightforward technical matter. Until last year, however, Japanese public opinion was firmly opposed to joining the nuclear club, with only 21% of Japanese supporting the idea, according to polls. Yet changes in the geopolitical landscape and the emergence of real threats could quickly shift public sentiment. The presence of nuclear weapons in South Korea would also be a significant factor for Japan. According to Rose, Australia is likely to follow these countries into the nuclear club. In the Middle East, the main candidates for nuclear armament are Iran, Saudi Arabia, and Turkey. Given the new geopolitical conditions, little is likely to deter them from adopting the opportunistic 'every nation for itself' approach. US ultimatums to Iran and offers of American nuclear protection to Saudi Arabia are also unlikely to be effective.

In the late 2000s, when the potential of nuclear deterrence already seemed largely exhausted, political scientist Kenneth Waltz proposed a new approach in an article entitled The Spread of Nuclear Weapons: More May Be Better. He argued that since maintaining the nonproliferation regime was unlikely, nuclear weapons should instead become accessible to a larger number of states. This, he suggested, would create a new system of multilateral mutual deterrence, reducing the likelihood of their use. However, Rose points out that the most dangerous phase of nuclear proliferation occurs when countries are on the verge of acquiring nuclear weapons or shortly after they cross that threshold. As a result, the world is likely to face a series of nuclear crises in the near future, similar in nature to the Cuban Missile Crisis of 1962, as new nuclear states test each other’s resolve or attempt to prevent their adversaries and neighbors from obtaining nuclear status.

While it is unlikely that the nonproliferation regime can be maintained in the form it existed in the second half of the 20th century, the world would undoubtedly be a safer place if the United States – the country with the largest nuclear arsenal – had a more responsible government. Such leadership would recognise its role in guiding the transition from the old nonproliferation regime, of which the US was once a key architect, to a new, balanced order that ensures greater global stability.