Participation in nuclear planning
With the exception of France, all NATO allies are members of the NATO’s Nuclear Planning Group (NPG), the alliance’s senior body on nuclear strategy. Their participation in nuclear strike planning entails an endorsement of the potential use of nuclear weapons in the future and thus an encouragement of the possession and development of nuclear weapons in the present. Participation in planning of temporally proximate use or threats to use nuclear weapons would amount to prohibited assistance for use or the threatening of use.
Japan and South Korea are engaged in ‘extended deterrence dialogues’ with the United States, covering conventional as well as nuclear deterrence. Japan and the United States met for an extended deterrence dialogue in Japan in November 2022.13 South Korea, for its part, reportedly ‘reactivated’ its extended deterrence dialogue in 2022 after a few years without actual meetings.
Any assessment of the compatibility with the TPNW of Japan’s and South Korea’s participation in extended deterrence dialogues is largely context-dependent. To the extent that such dialogue is on general nuclear deterrence where future use is theoretical, Japan and South Korea’s participation should be considered as encouragement of possession of nuclear weapons. To the extent that the nuclear-related dialogue concerns specific targets and is directed and communicated towards a specific adversary, it could also amount to assistance to threatening to use nuclear weapons.
If Japan and South Korea were to adhere to the TPNW in the future, they would have to provide assurances that their respective ‘extended deterrence dialogues’ with the United States would not involve nuclear planning.
The Marshall Islands, which is undecided on the TPNW, is the only non-nuclear-armed state that in 2022 permitted the testing of missiles designed to carry nuclear warheads on its territory. Allowing such testing is not consistent with the TPNW’s prohibition on assistance with development of nuclear weapons. The Marshall Islands hosts a test site that regularly serves as the destination point for US test launches of nuclear-capable long-range missiles. The site in question is the Ronald Reagan range at Kwajalein Atoll, a military station established after the Second World War. The land on which the site is located is leased to the United States through a long-term agreement. It is not the testing site in and of itself that conflicts with the TPNW, but the United States’ use of it to maintain and develop nuclear-weapon missile technology.
Having initially postponed such tests due to the risk of escalation associated with the Russian invasion of Ukraine, the United States launched Minuteman intercontinental ballistic missiles from Vandenberg Air Force Base in California to Kwajalein Atoll in August and September 2022. Should the Marshall Islands decide to adhere to the TPNW, such testing would need to stop if it involved nuclear-capable missiles. Marshallese adherence to the TPNW could thus lead to friction with the United States, perhaps helping to explain the Marshall Islands’ hesitancy about joining the Treaty. With its long history as a testing ground for US nuclear weapons, the Marshall Islands has been a strong supporter of nuclear disarmament and the campaign to end nuclear testing.
Also Kazakhstan, which is a state party to the TPNW, hosts a test site which has previously been the destination for test launches of nuclear-capable long-range missiles. The Sary-Shagan missile range was established by the Soviet government in 1956. There is no evidence that Russia used the Sary-Shagan site to test missiles designed to carry nuclear warheads in 2022. Sary-Shagan appears not to have been used as the destination point for intercontinental ballistic missile tests for some time now, possibly in reaction to Kazakhstan’s ratification of the TPNW. In fact, Russian officials have noted the problem of not having testing grounds on Russian soil, and Russia has begun constructing a new missile test site on Russian territory. That said, Russia announced in 2022 that it planned to launch missiles from the Kaputsin Yar range in Russia in 2023. Missiles launched from Kaputsin Yar have traditionally landed at the Sary-Shagan site.
As a state committed to the goals of the TPNW and the Central Asian Nuclear-Weapon-Free Zone (NWFZ) treaty, Kazakhstan should communicate its priorities to Russia and request that it continues to abstain from using the Sary-Shagan site to test any missiles designed to carry nuclear warheads (unless the sole purpose is to test the conventional capability of dual-capable missiles).
It has been suggested that the obligation in TPNW Article 4(2) to ensure ‘the elimination or irreversible conversion of all nuclear-weapons-related facilities’ obligates Kazakhstan to close the Sary-Shagan site. However, Article 4(2) applies to any state that ‘owns, possesses or controls nuclear weapons or other nuclear explosive devices’ and can therefore not be applied to Kazakhstan. To the extent that Sary-Shagan is ‘clearly connected to Russia’s nuclear weapon complex’, any responsibility to eliminate or irreversibly convert the Sary-Shagan test site under Article 4(2) would fall on Russia.
A total of 34 non-nuclear-armed states contravened Article 1(1)(e) of the TPNW in 2022 through specific nuclear-related doctrines, policies, and/or statements to which they subscribe. This concerns the 27 umbrella states in NATO; prospective NATO members Finland and Sweden; US allies Australia, Japan, and South Korea; and Russian allies Armenia and Belarus.
NATO’s foundational document, the North Atlantic Treaty, does not mention nuclear weapons, but every NATO member has supported possession and potential use of nuclear weapons through their endorsement of various other alliance documents, particularly the Strategic Concept, which was last updated in 2022. None of the alliance’s members has so far rejected the possession or use—or even the first use—of nuclear weapons on its behalf. In the view of the Ban Monitor, their endorsement of the Strategic Concept amounts to encouragement of possession of nuclear weapons. It does not, however, amount to encouragement of use, as that would require, for instance, a request for use of nuclear weapons in a specific context, or agreeing to rules of engagement allowing the use of nuclear weapons in a concrete multinational operation.
Two prospective NATO members, Sweden and Finland, submitted letters of intent in 2022 where they declared that they accept ‘NATO’s approach to security and defence, including the essential role of nuclear weapons’ and that they are ‘willing to commit forces and capabilities for the full range of Alliance missions.’ These documents, and several public statements in support of nuclear weapons by the governments of Sweden and Finland, are inconsistent with the TPNW’s Article 1(1)(e) as they encourage the possession of nuclear weapons by NATO members.22
Three non-NATO US allies (Australia, Japan, and South Korea) also encourage possession of nuclear weapons through explicit statements they have made or strategy documents they have endorsed. With respect to Australia, the most recent example of a government document which appears to directly encourage the United States to retain nuclear weapons was published in 2020, stating that ‘only the nuclear and conventional capabilities of the United States can offer effective deterrence against the possibility of nuclear threats against Australia.’
In addition to NATO, the Russian-led Collective Security Treaty Organization (CSTO) is understood by some observers as a ‘nuclear alliance’. In 2010, the CSTO’s Secretary-General suggested Russia had extended a ‘nuclear umbrella’ over all members of the alliance. Yet, CSTO members do not appear to have adopted official documents stipulating a nuclear dimension to the alliance. On the contrary, three members have actively distanced themselves from nuclear deterrence. Through the 2006 Treaty of Semipalatinsk—the treaty establishing Central Asia as an NWFZ—Kazakhstan, Kyrgyzstan, and Tajikistan have committed never to ‘assist or encourage’ the development, manufacture, or possession of nuclear weapons. As noted above, Kazakhstan is also a state party to the TPNW.
Belarus, however, which is allied to Russia through the CSTO and the Union State, has on multiple occasions expressed support for nuclear deterrence (including through requests to host Russian nuclear weapons on Belarusian soil) and is therefore not in compliance with the TPNW’s prohibition on encouragement of possession of nuclear weapons. Armenia, the last CSTO member, has, to the Ban Monitor’s knowledge, not explicitly endorsed the possession and potential use of nuclear weapons on its behalf. Armenia would, though, need to actively distance itself from nuclear deterrence in order to be considered compliant with Article 1(1)(e) of the TPNW, as fellow CSTO members Kazakhstan, Kyrgyzstan, and Tajikistan have already done through their adherence to the Treaty of Semipalatinsk, and in Kazakhstan’s case also to the TPNW.
Through their continued endorsement of nuclear deterrence, umbrella states contribute to the resolve of nuclear-armed states continuously to rebuild and maintain their nuclear capabilities. Nuclear-armed states often assert a need on behalf of non-nuclear allies and partners to ‘assure’ and fulfil ‘extended deterrence commitments’ as pretexts for their nuclear deployments and modernisation programmes, including the building of new capabilities