This month marks the 55th anniversary of the treaty on the non-proliferation of nuclear weapons (NPT), aimed at preventing the spread of nuclear weapons and facilitating nuclear disarmament.
The pact is signed by 191 countries, including the big five nuclear powers (USA, Russia, France, United Kingdom and China). It obliges states not to transfer nuclear weapons to any other state and commits the other states to agreeing not to acquire nuclear weapons. A rigorous monitoring system, under the aegis of the International Atomic Energy Agency, ensures compliance. Ireland paved the way for the treaty when, in 1961, it became the first state to propose to the UN General Assembly a ban on the transfer of nuclear technology.
Although India, Israel, North Korea and Pakistan have since joined the nuclear club, the NPT has proved remarkably successful in preventing the spread of such weapons and in preventing a collapse of deterrence strategies. This is remarkable bearing in mind US president John F Kennedy’s downbeat 1963 prediction of 25 nuclear-armed states by the 1970s.
Among the first to go nuclear may be Ukraine, notwithstanding the remarkable restraint displayed by Volodymyr Zelenskiy last week in the face of baiting by Donald Trump in the White House
But it’s doubtful whether this success can be continued in the coming years. Increased geopolitical tensions in Europe and Asia, and US disengagement from global security institutions, including the potential ending of its extended deterrence strategy whereby countries like Japan are permitted to shelter under its nuclear umbrella, make its future very uncertain.
Among the first to go nuclear may be Ukraine, notwithstanding the remarkable restraint displayed by Volodymyr Zelenskiy last week in the face of baiting by Donald Trump in the White House.
Were Ukraine to develop a nuclear capability, it would be returning to the position it occupied after the collapse of the Soviet Union in 1991. At that time, the newly independent country was the holder of the third-largest nuclear arsenal in the world. A series of agreements in the 1990s, particularly the 1994 Budapest Memorandum, meant it relinquished those weapons in exchange for guarantees from the United States, Russia, United Kingdom and France to respect its independence. Russia’s annexation of Crimea in 2014 and invasion of Ukraine eight years later laid bare the folly of Kyiv’s decision to do so, one which Zelenskiy has termed “stupid, illogical and very irresponsible”.
In October 2024, Zelenskiy said that he had told Trump that Ukraine would need nuclear weapons to secure its sovereignty if it could not join Nato. The following month, against the backdrop of Trump’s re-election and the possibility that he could withdraw military support from Ukraine, now unfortunately realised, a paper prepared for the Ukrainian ministry of defence suggested that the country could develop a crude nuclear device, akin to the “Fat Man” bomb dropped on Nagasaki in 1945, within months. Ukraine’s ability to develop such weapons is not in doubt. It has the technical know-how, derived from its legacy as a former Soviet state, and controls nine operational nuclear reactors from which to harvest the fissile material for warheads, including a supply of weapons-grade plutonium at Chernobyl.
More problematic, however, is that any attempt by Ukraine to develop its own nuclear deterrent could prompt Russia to use nuclear weapons against it
The near breakdown in relations between Washington and Kyiv, and Trump’s refusal to contemplate Nato membership for Ukraine, suggest that the country may now decide it has no option but to go down that path. This would require it to withdraw from the NPT, something only North Korea has done to date.
More problematic, however, is that any attempt by Ukraine to develop its own nuclear deterrent could prompt Russia to use nuclear weapons against it in an attempt to force a speedy end to the conflict on its terms – something that became a matter of acute concern in 2022 as a Ukrainian offensive threatened to rout Russian forces. The Kremlin backed down upon being told by the Biden administration via backdoor channels that this would result in “catastrophic” consequences for Russia, the prospect that Trump would maintain that policy is fanciful given his embrace of Putin.
The dilemma Ukraine faces could prompt non-nuclear weapons states to develop their own deterrent against aggression at the hands of prospective nuclear-armed foes. Incoming German chancellor Friedrich Merz, who has shown frankness and perspicacity in response to the threat Trump’s actions pose to Europe, has yet to go as far as that, suggesting instead that Germany might engage with France and the United Kingdom in “nuclear sharing”, including participating in the planning for the use of such weapons.
However, should Germany find itself without any nuclear safeguards, its traditional fears of encirclement, exacerbated by the prospect of being caught in a pincer movement between a revanchist Russia on the one hand, and a US administration which openly supports subversive political parties like the AfD on the other, could lead it to consider withdrawal from the NPT a price worth paying.
The South Korean foreign minister recently told his parliament that an independent nuclear deterrent was not ‘off the table’
In Asia, too, China’s expanding military and nuclear capabilities, together with its assertive territorial claims in the region, and the belligerent and unpredictable actions of its nuclear-armed protege, North Korea, may prompt Japan and South Korea to develop nuclear weapons. In pondering the old question as to whether the US would risk San Francisco for the sake of Seoul, South Korea may well conclude that it would not.
Both Japan and South Korea have advanced civilian nuclear programmes and the expertise to swiftly put them to military use. Japan is recognised as being no more than the turn of a screw away from possessing nuclear weapons, although its history as the only country to have been the subject of an atomic attack means that the majority of public opinion there is against developing them.
South Korea began a nuclear weapons programme in 1974. While this ended under American pressure two years later, Seoul has since experimented with the enrichment of uranium and plutonium, key components of nuclear bombs, and came under International Atomic Energy Agency investigation in 2004 on that account.
The South Korean foreign minister recently told his parliament that an independent nuclear deterrent was not “off the table”.
In the current climate, the outlook for continued success of the NPT seems bleak. Increased proliferation will result in reduced deterrence and the consequent likely use of nuclear weapons in anger this century. Should that happen, then for all of Trump’s alleged desire to prevent the third World War, it will be his thrashing of America’s postwar foreign policy and his willingness to throw traditional allies to the wolves that will be seen as having lit its touchpaper.
- Anthony Moore is a senior counsel and a member of the Bar of Ireland who practises in the area of human rights
