By Robert Patman & Luke Hazelton

The Treaty on the Prohibition of Nuclear Weapons (TPNW) is an important landmark in the continuing effort to establish a global ban on the use of nuclear weapons. New Zealand played a significant diplomatic role in the adoption of the TPNW at the United Nations General Assembly on 7 July 2017. The treaty seeks to totally eliminate all nuclear weapons and it comes into force on 22 January 2021. The Labour-led coalition government in New Zealand was the 14th state to ratify the TPNW in 2018

The emergence of the TPNW

In the eyes of many states, the 1968 Non-Proliferation Treaty (NPT) – which was extended indefinitely on 11 May 1995 – has not lived up to expectations. The NPT was based on an understanding between the nuclear weapon states (NWS) and the non-nuclear weapon states (NNWS) the NWS would in good faith purse the goal of ending the nuclear arms race and embrace nuclear disarmament. In return, the NNWS would not acquire nuclear weapons. However, despite the end of the Cold War in 1989, the NWS have failed to deliver on their commitment to eliminate nuclear weapons. Today, there are 14,000 nuclear weapons in the world and NWS, like the US, China and Russia, have continued to modernise their nuclear weapons capabilities.

In light of NWS’ failure to deliver their end of the bargain, the majority of states, in partnership with the International Campaign to Abolish Nuclear Weapons (ICAN) successfully negotiated the TPNW, and on 22 October 2019 122 states voted to adopt the Treaty. To date, the TPNW has been signed by a total of 84 states, 50 of which have ratified the treaty. As noted, New Zealand has strongly supported the TPNW. It encouraged other states to support and implement the treaty. In particular, Wellington worked closely with a number of Pacific states, resulting, for example, in Kiribati ratifying and Nauru signing the TPNW.  

Under the terms of TPNW, there is a strict prohibition on the use and possession of nuclear weapons. The treaty reflects a deep concern with the catastrophic consequences that will result from the use of nuclear weapons and also an awareness of the risks posed by their continued existence. All states that have signed the TPNW are required to their abolish nuclear-weapon programmes and other nuclear explosive devices, as well as dismantle all nuclear-weapon related facilities or convert them to use for alternative peaceful purposes. 

All states party to the TPNW must provide victim assistance and environmental remediation to those affected by the testing of nuclear weapons. Mutual co-operation and support are a mandatory part of the treaty, whether that be technical, material, or financial assistance. Signatories are also expected to encourage states currently outside the TPNW to sign, ratify, accept, approve or accede to the treaty.

The promise of the TPNW

It is difficult to exaggerate the potential importance of this treaty. The devastating power of nuclear weapons represents one of the greatest threats to human life on earth. While there has not yet been a case of full-blown nuclear warfare, there have been at least three occasions in the post-1945 era when the world teetered on the brink. The Cuban missile crisis of October 1962 was certainly the closest the world came to a nuclear showdown. At one stage in the crisis, the US President, John F. Kennedy, estimated the odds of nuclear war to be “somewhere between one out of three and even”. In addition, the Yom Kippur war of October 1973 briefly escalated to the level of nuclear confrontation between the US and the USSR, and a NATO exercise known as ‘Able Archer’ in November 1983 was initially interpreted by the Soviet leadership as a prelude to a nuclear attack and Moscow for seven days weighed the possibility of a nuclear response. 

The end of the Cold War in 1989 reduced the prospect of a global nuclear war, but the subsequent proliferation of states with a nuclear weapons capability and the rise of transnational terror organisations in the post-Cold War era that are actively seeking nuclear weapons means the nuclear threat is far from over. In this connection, Martin Hellman has argued some form of nuclear clash is almost inevitable in the long run unless the possession of nuclear weapons is reduced to a level approaching zero. This shows that what is at stake with the TPNW is a concern that affects humanity as a whole.

Prior to the emergence of the TPNW, nuclear weapons were among the few weapons of mass destruction that were not subject to a categorical ban. And this was despite the evidence of the calamitous humanitarian consequences occasioned by the American use of atomic bombs at Hiroshima and Nagasaki in August 1945. The TPNW will help to close the existing loopholes in international law regarding nuclear-weapons and nuclear-explosive devices. After ratification by more than 50 states, the TPNW has become part of international humanitarian law and created a legal norm against the possession of nuclear weapons. Such norms matter if the experience of prohibiting other types weapons is anything to go by. 

For instance, the 1993 Chemical Weapons Convention (CWC) has resulted in all of the 97 declared chemical weapons production facilities being either deactivated or converted to civilian use. This example provides considerable grounds for optimism with respect to what the TPNW hopes to achieve concerning the elimination of nuclear weapons.

The potential pitfalls of the TPNW

One of the main criticisms against the TPNW is its alleged incompatibility with the previously mentioned, NPT. Strictly speaking, the TPNW seeks to make nuclear weapons illegal for all states, whereas the NPT effectively enabled the five countries that had proliferated before 1968 to exercise a monopoly on nuclear weapons thereafter. Despite the clear expectation that these NWS would subsequently disarm themselves, their exceptional nuclear status has provided a legal loophole that is not easy to close. As stated in Article 18 of the TPNW: ‘The implementation of this Treaty shall not prejudice obligations undertaken by State Parties with regard to existing international agreements, to which they are party, where those obligations are consistent with the Treaty’. As previously stated, there is no time-limit attached to the NPT. Therefore, the five NWS states whose status was explicitly recognised by the NPT could claim that they have some discretion in fulfilling their commitment to disarmament and could not join the TPNW without undermining the original NPT. 

There are two other criticisms against the TPNW. The first is the practical challenge concerning the abolition of nuclear weapons or the facilities supporting them. There is nothing in the treaty that spells out the actual process for achieving these goals. Rather, the onus seems to be on NWS deciding how they might dismantle such capabilities. While there is mandatory mutual assistance is specified under Article 4 of TPNW, this is may be difficult to implement, especially considering the disruptive global impact COVID-19 has had over the past year and will probably continue to have into 2021. A second possible problem of the TPNW is identified by Michael Rühle. He questions the logic “that social norms can be as important as legal ones”. By reinforcing the stigmatisation of nuclear weapons, the TPNW tends to assume NWS will face increased pressure to join treaty because of the risk of being seen as pariah states in the international community if they do not. But NWS may well see such capabilities as vital for their national security and would be reluctant therefore to run the risk of a greater sense of national vulnerability in order to uphold an emerging consensus against nuclear weapons. In this respect, Rühle compares the abolition of nuclear weapons with the abolition of slavery. While there has been a global social norm against slavery as well as legal provisions against its practice, the number of slaves is estimated to be higher today – almost 30 million in total – than at any time during human history.

Conclusion: The TPNW and reframing of the nuclear weapons threat

While the TPNW will not immediately resolve the global threat of nuclear weapons, it is a very positive step toward reframing the debate on the relationship between the possession of nuclear weapons and international security. To date, the NPT has failed to create an environment in which the major stockpilers of nuclear weapons – which also happen to be the five permanent members of the UN Security Council (the United States, China, Russia, the UK and France) – feel any great pressure to embark on the path of serious disarmament. Moreover, the apparent unwillingness of these five states to scrap their own nuclear weapons arsenals makes the task of curbing nuclear weapons proliferation elsewhere more difficult. 

‘Hold out’ NWS like India, Pakistan and Israel have refused to join the NPT and have indicated they will not do until the five permanent members of the UN Security Council show a willingness to dismantle their own nuclear weapons capabilities. The emergence of the TPNW signals that the vast majority of states believe the current nuclear weapons situation  is both dangerous and unacceptable, and that the five major nuclear weapons states can now expect to be increasingly challenged by a growing number of states, including New Zealand, over their right to dictate the terms of global security. In the short term, the five major NWS will almost certainly oppose the TPNW, but in the long term the political and diplomatic costs of the NWS continuing to insist they alone must retain nuclear weapons could prove, in the face of growing international pressure, to be prohibitively high.


Robert Patman is a Professor of Politics at the University of Otago. He is an expert in international relations and global security. 

Luke Hazelton is a Masters student in International Studies at the University of Otago. 

Disclaimer: The views expressed in this article reflect the author(s) opinion and not necessarily the views of The Big Q. 

See Also:

Q+A: Banning the bomb: Are the days of nuclear weapons numbered?

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