The obligation to eliminate nuclear weapons
None of the world’s current nuclear-armed states chose to participate in the negotiation of the TPNW or its adoption, and to date, none has adhered to the Treaty. The Treaty provides two pathways to their future adherence: one for so-called destroy-and-join states (‘Article 4(1) states’), and a second for so-called join-and-destroy-states (‘Article 4(2) states’).
- Article 4(1) of the TPNW obligates states parties that after the adoption of the TPNW on 7 July 2017 owned, possessed or controlled nuclear weapons or other nuclear explosive devices, but eliminated their nuclear-weapon programmes (including the elimination or irreversible conversion of all nuclear-weapons-related facilities) before becoming party to the TPNW, to cooperate with the competent international authority designated by the states parties, for the purpose of verifying
that its nuclear-weapon programme has been irreversibly eliminated. - Article 4(2) of the TPNW obligates states parties that continue to own, possess, or control nuclear weapons or other nuclear explosive devices upon becoming party to the Treaty, to immediately remove the weapons or devices from operational status and to destroy them as soon as possible but not later than a deadline to be determined by the First Meeting of States Parties. The process of destruction must be detailed in a legally binding, time-bound plan that provides for the verified and irreversible elimination of that state party’s nuclear-weapon programme, including the elimination or irreversible conversion
of all nuclear-weapons-related facilities. Such a state must submit a draft of the plan to the other states parties or to a competent international authority they designate within 60 days of becoming a party. The plan must then be negotiated with such an authority and submitted to the next meeting of states parties or review conference, whichever comes first, for approval. - To prevent re-armament, both the so-called destroy-and-join states and the join-and-destroy states are also obliged to conclude a Safeguards Agreement with the IAEA sufficient to provide credible assurance of the non-diversion of declared nuclear material from peaceful nuclear activities and of the absence of undeclared nuclear material or activities. For the interpretation and information on this, please refer to the previous section on the obligation to have Safeguards Agreements and Additional Protocols with the IAEA.
The TPNW helps create the conditions for nuclear disarmament, and synergistic political processes can spring from it. Some of today’s nuclear-armed states might be influenced to disarm on a unilateral basis, while others might be willing to engage in bilateral or multilateral negotiations that could lead to the elimination of their respective arsenals. Disarmament is possible.
Historically, only ten states have manufactured some form of nuclear explosive device. One of them, South Africa, subsequently disarmed. South Africa produced nuclear weapons in the late 1970s but decided in 1989 to give up its nuclear- weapons and acceded to the NPT as a non-nuclear-weapon state in 1991. In 1994, the IAEA confirmed that South Africa had converted its nuclear programme to exclusively peaceful applications. Three states – Belarus, Kazakhstan, and Ukraine – acquired the nuclear weapons they had hosted on their territories when the Soviet Union collapsed, but voluntarily handed them over to Russia for destruction with the support of the United States and joined the NPT as non-nuclear-weapon states in the 1990s.
According to the Federation of American Scientists, the number of nuclear weapons in the world peaked in 1986 at around 70,300 warheads (see the figure below). That number was subsequently hugely reduced, and in September 2020 the global estimate was of 13,410 nuclear warheads remaining.
The overwhelming portion of this reduction in nuclear-weapon stockpiles took place in the 1990s, and nearly all of the reduction occurred in the massive US and Russian arsenals (but there were reductions in France and the United Kingdom as well, and, as noted above, South Africa destroyed its entire (small) arsenal of nuclear explosive devices). The reductions made by the United States and Russia thus far have mostly been results of arms control agreements and stockpile management, and did not form part of a coherent plan to ‘ultimately eliminate’ such weapons. The pace of nuclear reductions has also slowed considerably since the 1990s, as illustrated by the figure below. China, India,
North Korea, and Pakistan appear to be increasing their weapon stockpiles. And despite their repeated claims that they are pursuing nuclear disarmament, there have been no negotiations about total nuclear disarmament between the United States and Russia since the Reagan–Gorbachev summit in Reykjavik in 1986, or even on reductions to 1,000 nuclear weapons each.
Setting a Deadline for Destruction
In accordance with Article 4, the First Meeting of States Parties to the TPNW is explicitly obligated to set a deadline for the destruction of a state party’s nuclear explosive devices. The Nuclear Weapons Ban Monitor recommends that it considers setting a deadline of ten years, renewable upon request to the other states parties where necessary. In ten years, it may be feasible to achieve elimination of even the largest nuclear-weapon stockpiles (those of the United States and Russia), as explained in an article in the Journal for Peace and Nuclear Disarmament by Moritz Kütt and Zia Mian.
Designating the International Authority or Authorities
Article 4(6) of the TPNW establishes that the states parties shall designate a ‘competent international authority or authorities’ to negotiate and verify the irreversible elimination of nuclear-weapons programmes of destroy-and-join states and join-and-destroy states. The need for a dedicated organisation tasked with the international control of disarmament has been discussed for decades. The TPNW provides a framework within which such a regime for nuclear disarmament can emerge, despite the fact that current member states have limited financial and technical resources and despite (or perhaps even because of) initial opposition from nuclear-weapon states.
The TPNW explicitly assigns some verification responsibilities to the IAEA. Several experts have suggested that the states parties to the TPNW should establish one or more new authorities in addition to the IAEA, which would cooperate with the IAEA and other relevant organisations through a division of tasks. One group of experts at Princeton University and Harvard University has recommended a phased approach, with the early establishment of a two-part organisational structure, comprising an implementation support unit and a dedicated scientific and technical advisory body. This would enable substantive work to identify implementation and verification challenges and finding solutions by the time one or more nuclear-weapon states join the Treaty, and the structure could then be scaled-up.
Verifying elimination under the TPNW
Whether future elimination of nuclear weapons and nuclear-weapon programmes will be implemented under one or more disarmament treaties complementing and implementing both the NPT and the TPNW, or whether it will take place within the TPNW, verification will play an important role.
As yet, no internationally agreed measures exist for verification of destruction and elimination of nuclear weapons, under any treaty. As illustrated in the figure below, the TPNW is the first and only legally binding multilateral instrument that requires verification of nuclear disarmament and elimination.
All states that join the TPNW while still in possession of nuclear weapons must negotiate a legally binding, time-bound plan that provides for the verified and irreversible elimination of that state party’s nuclear-weapon programme, including the elimination or irreversible conversion of all nuclear-weapons-related facilities. And all states that have disarmed before joining the TPNW must demonstrate to a competent international authority to be designated by the states parties to the Treaty that the weapons and programmes have been eliminated.
The TPNW’s entry into force means that it is important now to lay the ground work so that, as soon as possible, it can accommodate one or more nuclear-armed states that may come to conclude that their national security would not be jeopardised by decreasing and finally eliminating their arsenal, and that taking such steps within the framework of the TPNW would provide assurance to the world of its actions. Building a system for the verification of the disarmament obligations in the TPNW is an important challenge which will be on the agenda of the meetings of states parties to the TPNW in the years ahead.
The following table presents the verification missions that it can be assumed will be needed in order to satisfy the TPNW’s requirements for verification.
