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To win support for ridding the world of nuclear weapons, the onus is on advocates to present a credible case for doing so (Manuel Elias/UN Photo)
Advocates need to answer six hard questions if they want to advance the goal of eliminating nuclear weapons.
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The nuclear ban treaty isn’t winning over the states that matterThe nuclear ban treaty isn’t winning over the states that matter
It’s been five years since the Treaty on the Prohibition of Nuclear Weapons entered into force. The first Review Conference will be held later this year for this international agreement banning member states from developing, possessing, using, threatening to use, or hosting nuclear weapons – a chance to assess progress and plan for future implementation.
On the surface, things look good for the Ban Treaty. In December 2025, 62% of UN member states voted in favour of a resolution calling upon “all States that have not yet done so to sign, ratify, accept, approve or accede to the Treaty at the earliest possible date”. Despite this majority support, however, the treaty is failing to win over one key constituency: those that actually depend on nuclear weapons for security.
In the same UN vote, of the nine states that possess nuclear weapons and the further 32 that exist under extended nuclear deterrents (the NATO members plus Australia, Japan, and South Korea), the best the Ban Treaty could muster was a single abstention from Australia.
This suggests that the Ban Treaty is not resonating with those that actually control nuclear weapons policy. These are the countries that would have to bear costs to advance the Treaty’s mission, for example in reforming national security policy, decommissioning nuclear assets, and standing up conventional alternatives to nuclear weapons.
Ban Treaty advocates need to demonstrate to nuclear-armed or nuclear protectorate states the same level of security is achievable without nuclear weapons.
Ban Treaty advocates flatly declare a strategy of nuclear deterrence to be a “scam”. But to win support for ridding the world of nuclear weapons, the onus is on them to present a credible case for doing so, which means engaging with complex questions. Take these six.
Ban Treaty advocates often emphasise the “unimaginable and catastrophic destruction” from nuclear use. A major nuclear war could certainly generate such effects. Yet options for nuclear use do fall below the Strangelovian threshold of an arsenal-emptying exchange between nuclear-armed superpowers. Battlefield nuclear strikes, demonstration strikes or nuclear use for area denial all involve the discriminating use of nuclear weapons for contained political and military effects. Do such options make certain, limited applications of nuclear weapons tolerable? Or would even such limited strikes be “catastrophic”, for example because they carried an unacceptable risk of escalation to an apocalyptic nuclear exchange?
Ban Treaty advocates dismiss nuclear deterrence as a net strategic disadvantage because “any potential benefits are far outweighed by the catastrophic risks of nuclear accidents or war”. Sustaining this argument requires demonstrating that nuclear deterrence is prone to failure. Under certain conditions, nuclear deterrence could fail – when nuclear deterrent capability is immature for example, or the stakes of a conflict are seen as minor. But where nuclear weapons capabilities are mature and stakes are significant, nuclear deterrence has consistently restrained conflict. The absence of major, direct wars between the Soviet Union and NATO, Russia and NATO, the United States and China, India and China, and India and Pakistan all suggest that risks of nuclear escalation loom large for decision makers. To make the Ban Treaty persuasive, advocates need to demonstrate that such apparent instances of deterrence success were either flukes, not replicable, or caused by non-nuclear factors.
What of the threat of “accidental nuclear war”? Even if nuclear deterrence is working as intended, technological failures or errors in judgement may lead to false-positives or miscalculations that inadvertently result in nuclear use. To be sure, such risks are very real. But unmanageable? New and emerging technologies such as cryptographic permissive action links, AI-powered command and control, and space-based early warning have the potential to provide resilience to nuclear command and improve crisis decision making. Will such capabilities relegate nuclear near-misses to the dustbin of history, or do they themselves open up new vulnerabilities?
The Ban Treaty assigns equal priority to the elimination of nuclear weapons across all nuclear-armed states. Whether France or Pakistan, United States or North Korea, the nukes must go as soon as possible. Such an indiscriminate approach arguably overlooks the differing risk profiles attached to certain nuclear weapons programs. Some nuclear-armed states might, for example, use their nuclear weapons for more objectionable end-uses than others. Some nuclear-armed states might be more at risk of nuclear deterrence failure or inadvertence than others. Some nuclear weapons programs may offset demand for other, equally objectionable capabilities such as biological and chemical weapons. And having some nuclear-armed states might actually prevent the emergence of new nuclear weapons programs.
Ban Treaty advocates need to demonstrate to nuclear-armed or nuclear protectorate states the same level of security is achievable without nuclear weapons. Precision strike systems, massive conventional ordnance and leadership decapitation strikes can emulate the political and military effects of nuclear weapons. It’s far from certain, however, that they can fully substitute for the latter’s “revolutionary” effects.
Ridding the world of nuclear weapons will require an unprecedented commitment of resolve, capital and technology. This is not just in the will of the nuclear-armed states to bear the financial and security costs of nuclear disarmament. It also requires a near-perfect ability to detect undeclared nuclear activities and the capability and will to intervene – militarily if necessary – to stop defection and cheating. Measuring success against this standard begs the question: is such a venture possible? Is the probability of success high enough and the benefits certain enough that nuclear-armed states are justified in taking this leap of faith?
By their votes, the states that matter have made clear that Ban Treaty advocates have a long way to go in building the case for abolishing nuclear weapons. This leaves the treaty itself in danger of failing to have a material influence on international nuclear weapons policy. And by the time its next Review Conference rolls around, the Ban Treaty will be in no better position than it is now.
About the author
Christopher J. Watterson
Dr Christopher J.
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