After the disintegration of the Soviet Union, Ukraine inherited the third-largest nuclear arsenal in the world. It, however, decided to give up its nuclear weapons, and instead opted to sign the NPT and subsequently gained security and economic assurances from the major powers. The United States, Russia, and the United Kingdom, under the Budapest Memorandum, assured Ukraine that its territorial integrity and sovereignty will not be harmed. Russia is currently in clear violation of this memorandum, and the dilemma is that assurances, unlike guarantees, are not legally binding and do not oblige the major powers to intervene militarily on Ukraine’s behalf. Now one prevailing idea is that this invasion could have been prevented if Ukraine never gave up its Soviet nuclear weapons because then, nuclear deterrence, which entails the threat of mutual destruction, would prevent the attack.

The statement by Pavlo Rizanenko, a member of the Ukrainian Parliament, while talking to USA Today, reflected this assumption. According to him, “Now there’s a strong sentiment in Ukraine that we made a big mistake,” He added, “In the near future, no matter how the situation is resolved in Crimea, we need a stronger Ukraine…If you have nuclear weapons, people don’t invade you.” Statements like these manifest the opinion that giving up nuclear weapons was a mistake on Ukraine’s part, and that, had these weapons not been given up, the Russian invasion would not have happened. But the important question here is how effective of a deterrent would these nuclear weapons serve against Russia, had they not been given up, and whether they would be credible enough to prevent the Russian invasion of Ukraine.

There is a widespread assumption that the deterrence associated with nuclear weapons automatically provides a guarantee against an attack. Historical examples do not support this claim. There have been instances where nuclear deterrence has prevented crises from being escalated to full-fledged wars, but conflicts and limited wars have still happened. Taking Kargil War as an example, two nuclear powers, India and Pakistan, engaged in a war with each other. Both had nuclear weapons, but these could not prevent them from fighting directly with each other. Also, apart from deterrence, the culmination of Kargil War had other factors, such as diplomacy, involved. Though nuclear deterrence might have prevented the war from posing an existential threat to either country, deterrence may fail when a state’s vital interests are threatened, and there is no guarantee that a state will not use nuclear weapons to secure them.

Therefore, there is no reason to suggest that had Ukraine not given up its nuclear weapons, the Russian invasion would not have happened. Nuclear deterrence would have limited effectiveness here. Nuclear weapons can prevent escalation, but they cannot provide a guarantee against an attack, especially when vital state interests are threatened. Deterrence works on the principle of rationality, but rationality may vary from state to state. One can never predict the decisions a state might consider rational when its vital interests are under threat.

Seeing the situation under the theoretical lens of international relations, realism suggests that states cannot be sure of the intentions of other states, and perceive them in the worst light. States are very sensitive to the security environment around them, and in the anarchic international system, self-help is the only way to protect themselves. Even if Ukraine did not have any malign intentions towards Russia at the moment, this might not always be the case. The threat of having a major adversarial bloc, in the form of NATO, just near its borders, and perceiving NATO’s enlargement to the East and Ukraine’s ambitions of joining NATO as a threat to its vital interests, Russia could still have invaded Ukraine, whether or not it had nuclear weapons. Nuclear weapons either way do not provide a guarantee against an attack. Thus, the decision to invade Ukraine might have seemed rational to Russia, when it needed to protect its borders.

Also, the possession of nuclear weapons by Ukraine could have made the situation worse, rather than stable. Consider Ukraine had nukes, and the conflict started, there is no reason to suggest that in the fog of war, one state would not launch its nuclear weapons.

This idea asserts that nuclear weapons, while not always effective in preventing an attack, are still effective in preventing the escalation of the crisis, but it is important to take historical context into focus here. Would the idea of Ukraine not giving up Soviet nuclear weapons be possible for it politically and technically at that time?

It is important to acknowledge first that the nuclear weapons Ukraine possessed were never really their own. The launch codes and command and control over the weapons remained with Moscow. Without effective control over the weapons, the Soviet nuclear weapons in Ukraine would lack credibility and could have never served as an effective or even a practical deterrent against future foreign aggression, and given the economic and financial instability of the country, and the lack of appropriate infrastructures then, it seems rather unlikely that Ukraine could have managed to gain independent control over the weapons or maintained them. Thus, the effectiveness of the deterrent is highly doubtful when even the practicality of the weapons is questionable.

Moreover, Ukraine had more to gain than to lose, by giving up its nuclear weapons. The newly independent state was undergoing a political and financial crisis. Giving up nuclear weapons allowed it to sign international treaties, gain economic and security benefits, and improve its relations with the international community. Politically too, US and Russia would not have wanted a state attempting to seize control over nuclear weapons. In short, Ukraine had to give up its nuclear weapons to ensure the political and economic stability of the country. It thus opted to use these weapons as a bargaining chip to gain benefits for itself.

Therefore, though the idea of possession of nuclear weapons seems very attractive, Ukraine at the time of its independence, was not capable of maintaining these nuclear weapons, and therefore the practicality of those weapons would be a matter of concern, let alone their use as a deterrent. Moreover, the belief that these weapons could have prevented the Russia-Ukraine war had Ukraine still somehow managed to gain control over them and maintained them, is not entirely refutable, however, it is important to note that while nuclear deterrence might have prevented the escalation, there is no guarantee that it would have prevented the Russian invasion, as many historical pieces of evidence prove otherwise. However, as the nuclear weapons on Ukrainian territory were never operationally its own, it could have used the opportunity to bargain in a better way, to get strong security guarantees from major powers. Then it could have got the space to choose whatever bloc it wanted to align with.