In the early 1990s, newly independent Ukraine briefly possessed more nuclear warheads than China, France and Great Britain taken together. It had inherited from the USSR some 1,900 strategic and 2,500 tactical nuclear weapons. However, Kyiv decided, against the background of the 1986 Chornobyl disaster, that Ukraine would become entirely free of nuclear weapons.
To be sure, Ukraine was unable to use most of its nuclear weapons. Yet, the amount of warheads, specialized technology and engineering expertise it had accumulated in the Soviet period was such that it could have preserved a small amount of enriched uranium or/and plutonium, or even nuclear ammunition and warheads. Under considerable pressure not only from Moscow but also with the generous help from Washington, Kyiv transferred its Weapon of mass destruction (WMD) arsenal, however, completely and quickly to Russia. Ukraine signed and ratified the Nuclear Non-Proliferation Treaty (NPT) as a non-nuclear weapon state.
In addition, Washington, Moscow, and London agreed to provide, in return for Ukraine's denuclearization, additional security guarantees based on the NPT's general guarantees. This happened at the December 1994 summit of the Conference for Security and Cooperation in Europe and emerging OSCE in Budapest. Kyiv as well as the Depositary Governments of the Russian Federation, United States and United Kingdom signed the – by now, famous – Budapest “Memorandum on Security Assurances in connection with Ukraine's accession to the Treaty on the Non-Proliferation of Nuclear Weapons.” In this document, the non-proliferation regime’s three guarantor powers, the RF as the legal successor of the USSR, UK and U.S., assured Ukraine of the security of its sovereignty and territory, as well as freedom from economic and political pressure.
The two other official nuclear-weapon states under the NPT, China, and France, followed suit. They provided Ukraine with separate governmental declarations expressing their respect for Ukraine’s sovereignty and integrity. Similar documents were provided to Belarus and Kazakhstan. These two other post-Soviet states, apart from Russia and Ukraine, also had inherited parts of the Soviet nuclear arsenal. Minsk and Almaty also agreed to transfer their WMDs to Russia.
The NPT – to which 191 States have joined, more than any other fundamental disarmament agreement – was opened for signature in 1968. It entered into force in 1970 and was extended indefinitely in 1995 – not the least against the background of the successful denuclearization of Ukraine, Belarus, and Kazakhstan. The goal of the treaty is to avert the spread of nuclear weapons, foster cooperation in the peaceful uses of nuclear energy, and work towards complete nuclear disarmament.
The NPT is the bedrock of the global nuclear non-proliferation regime. It contains the only binding commitment, in a fully ratified multilateral treaty, the goal of disarmament by the nuclear-weapon states. The agreement addresses the issue that preventing the proliferation of nuclear weapons cannot be achieved by individual states. It requires the dedication and collaboration of the global community.
The NPT contains the obligation of nuclear-weapon states to not transfer WMDs to other states (Article I) and of non-nuclear-weapon states to not receive, manufacture or acquire nuclear weapons (Article II). It includes a promise of nuclear-weapon states to help promote the development of civilian nuclear applications of all treaty parties (Article III). It also documents a pledge of the nuclear-weapon states to work towards disarmament (Article IV). In its preamble, the NPT recalls “that, in accordance with the Charter of the United Nations, States must refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any State.”
The effect of the non-proliferation regime has so far been that the world’s vast majority of developed states have abstained from acquiring atomic arms. Outside the NPT, only Israel, India, Pakistan, and North Korea have developed their own nuclear weapons capacities. However, their arsenals are smaller than those of the NPT’s five official nuclear-weapon states and permanent UN Security Council members – Russia, the U.S., France, the UK, and China. More than five decades after its signing, the NPT remains thus largely intact. Its tenth review conference is scheduled for later this year after several postponements due to the pandemic.
With Russia’s military as well as non-military (“hybrid”) attack on Ukraine and annexation of Crimea since 2014 and its massive escalation in 2022, the Kremlin has put the logic of the non-proliferation regime on its head. It looks now as if the NPT’s purpose is to keep weak countries defenseless and prey to nuclear-weapon states. The treaty’s exemptions provide the NPT’s five official nuclear-weapon states – incidentally, also the world’s strongest conventional military powers – with an opportunity to extend, at low cost, their officially claimed state territories. They can do so at the expense of smaller nations governed by naïve believers in the rule of international law, and signatories of the NPT as non-nuclear-weapon states.
Russia’s behavior since 2014 and massive assault in 2022 represents not only a menace towards Ukraine and other neighbors. It is also a threat to the integrity of the NPT and the global order of which it is a foundation, and on which the security of 191 states, including Russia itself, depends. The deterioration of the NPT lessens worldwide faith in the plausibility of the nonproliferation goals, diminishes the will of individual states to participate in their pursuit, and increases the potential and temptation for additional states (and non-state actors) to acquire nuclear weapons. It thus erodes the security of all.
What long-term psychological effects will the behavior of Russia vis-à-vis Ukraine have? An NPT depositary and official nuclear-weapon state, as well as UNSC permanent member, attacks a fully denuclearized, yet formerly atomic country. The repercussions of this decision on the thinking of current and future political leaders and strategists around the world may be deep.
The fateful events since 2014 - Russia’s brazen annexation of Crimea and pseudo-civil war in Eastern Ukraine as well as the West’s timid and belated reactions to these aberrations – were already suggestive. In 2022, Moscow was able to attack as unapologetically as it did Ukraine because Russia is a nuclear-weapon state. The Russian Federation is officially allowed to possess nuclear weapons while Ukraine does not only not have but is officially forbidden to obtain them.
These circumstances may be especially noteworthy for various middle powers which currently do not possess WMDs, yet either control or eye territories claimed by neighboring states. Countries that have the potential capacity and a realistic chance to obtain and sustain nuclear weapons may, after 2014, think twice. Does it really make sense to rely on international law, in general, and the NPT, in particular?
Current and future governments of middle powers not integrated in larger alliances such as NATO may learn three simple lessons. First, it is good to have, unlike Ukraine, nuclear weapons. Second, it is not good to give them, like Ukraine, away. Third, it is not good to rely on bi- and multi-lateral treaties, memoranda, assurances, and other verbal statements – even if they are fully ratified or/and supported by the leaders of the world’s most powerful countries.
Instead, you should follow a wiser policy than Kyiv did in the early 1990s when it gave away all the Ukrainian warheads and nuclear material. Instead, your country’s chances to keep its territorial integrity will be higher than Ukraine’s, if you build, obtain, and keep nuclear warheads. Once a new disruptive technology makes it feasible to develop or buy nuclear weapons, you may want to get them. That is especially wise if you have rapacious neighbors that will also do so, or which already have WMDs.
Moreover, you may - as happened in 2014 - get the chance to snatch a piece from a neighboring state that is naive enough to lack sufficiently deadly weapons and blindly trusts international law. The only thing you must do is wait patiently until a convenient time to take military action. You need to carefully prepare as well as spread a semi-plausible narrative for executing your territorial expansion.
You also must make the world believe that you are ready to resolutely use nuclear warheads once necessary. To defend your new territorial acquisition, you will, if push comes to shove, be ready to use all your military capabilities. As Russia since 2014, you can then be assured that no outside powers will directly help any of those non-nuclear neighbors you have chosen to attack.
Further on, you can hope that you may not face any noteworthy sanctions at all, if you declare your newly obtained territories “independent states,” as Moscow did with Georgia’s Abkhazia and “South Ossetia” in 2008. Or you may decide that you are ready and have the capacity to deal with some mild sanctions, like Russia since 2014. Then you can even formally annex your neighbor’s occupied area, such as Russia did with Ukraine’s Crimea, to your nuclear-weapon state’s territory. Or you may decide to play va banque, like the Kremlin did in 2022. Whatever you decide – you yourself are fundamentally safe. Your troops will not face direct resistance from third powers on the territory of your aggression’s victim, as everybody will be afraid that you could nuke them.
Alternatively, you can engage non-submissive neighbors over years, sometimes in high-intensity, sometimes in low-intensity conflicts, with semi, or fully regular troops. If you choose to not escalate too much, like Russia until 2022, you also have reasons to hope that any sanctions possibly imposed can be circumvented, weakened, or abolished over time. The latter happened, for instance, regarding the minor EU sanctions regarding Russia’s behavior in Georgia in 2008.
Finally, as the post-Soviet republics’ experience with Russia of the past 30 years has shown, as a nuclear-weapon state you have other options to encroach, subvert and undermine recalcitrant "near abroad" with impunity. You may do so with special service operations, political warfare, cyberattacks etc. You only need to have enough WMDs to seriously scare the world. Then you can calculate that no military action by more powerful international actors will ever be taken against your country. What else do you need to know to get the bomb as soon as possible?
 Maria Rost Rublee, "From the Archive: Ukraine - a Fantasy Counterfactual," IISS (2 March 2022). https://www.iiss.org/blogs/survival-blog/2022/03/from-the-archive-ukraine-a-fantasy-counterfactual
 Polina Sinovets and Mariana Budjeryn, Interpreting the Bomb: Ownership and Deterrence in Ukraine's Nuclear Discourse, Wilson Center (December 2017). https://www.wilsoncenter.org/publication/interpreting-the-bomb-ownership-and-deterrence-ukraines-nuclear-discourse
 Mariana Budjeryn and Polina Sinovets, "Denuclearization again? Lessons from Ukraine's Decision to Disarm," War on the Rocks, 19 April 2018. https://warontherocks.com/2018/04/denuclearization-again-lessons-from-ukraines-decision-to-disarm/
 United Nations Office for Disarmament Affairs, Treaty on the Non-Proliferation of Nuclear Weapons (NPT). https://www.un.org/disarmament/wmd/nuclear/npt/
 United Nations - Tenth Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). https://www.un.org/en/conferences/npt2020/media-center-and-news
Andreas Umland and Hugo von Essen are analysts with the Stockholm Centre for Eastern European Studies (SCEEUS) at the Swedish Institute of International Affairs (UI). Jakob Hallgren, Director of UI, made useful comments on an earlier version of this text. Responsibility for all remaining imprecisions lies with the authors.