Russia’s invasion of Ukraine has substantially worsened global nuclear security. A major consequence of the Ukraine war has been to intensify Western fears of nuclear war. Russian leaders have made frequent threats, some explicit, to use nuclear weapons due to Ukraine-related developments.
When announcing the invasion in February 2022, Russian President Vladimir Putin warned countries considering military intervention on Ukraine’s behalf that they would face “consequences … such as you have never seen in your entire history.” At the end of September, Putin menacingly observed that the United States had created a “precedent” by dropping atomic bombs on Japan in 1945 to end a war. Earlier this year, Putin stated that Russia and Belarus would establish conditions for the potential return of Russian nuclear weapons in Belarus.
Challenges to NATO security
NATO governments have denounced Russian rhetoric as recklessly provocative and criticized Russian actions for raising the risk of nuclear escalation and war. In their view, Russia has violated the Nuclear Nonproliferation Treaty through its threats, disregarded the assurances provided to Ukraine in the Budapest Memorandum, and elevated the prospects of an accident at Ukraine’s nuclear power plants by conducting military actions in their vicinity. Western leaders have warned that Russian use of nuclear weapons in Ukraine would be “a game changer” that would fundamentally alienate Russia from the world.
Still, Russian policymakers may have plausibly concluded that their threats of nuclear use will limit the U.S. and allied response to their aggression. Western governments have augmented military deployments in front-line NATO countries, applied economic and diplomatic sanctions on Russia, and provided substantial military training, arms deliveries, and non-military assistance to Ukraine. They have declined, however, to intervene directly in the fighting with their combat forces. For example, fears of nuclear escalation weighed against Ukrainian requests that NATO enforce a no-fly zone over Ukraine or provide sophisticated long-range strike weapons.
Growing nuclear proliferation risks
From the perspective of further nuclear weapons proliferation, Russia’s invasion of Ukraine has potentially incentivized other countries to seek nuclear arsenals. The war has highlighted the limited value of vague security guarantees given to states, like Ukraine, that have abstained from pursuing their nuclear weapons in return for general pledges of support from other countries—in Ukraine’s case, the 1994 Budapest Memorandum. Due partly to Russian aggression against Ukraine, the most recent NPT Review Conference was exceedingly contentious. Russian diplomats blocked the draft final outcome document due to its critical wording regarding Russia’s disregard for nuclear safety principles at Ukraine’s Zaporizhzhia Nuclear Power Plant.
Russian policies regarding the Iranian and North Korean nuclear programs have changed due to their governments supporting Russian military operations against Ukraine, along with the deterioration in Russian-U.S. relations. Before the Ukraine crisis, Russia and Western governments regularly cooperated bilaterally and in multilateral structures to prevent Iran and North Korea from pursuing nuclear weapons. Such collaboration has decreased since the Russian invasion. For example, the Russian government has declined to support additional sanctions on either country despite their violating their nonproliferation obligations and UN Security Council resolutions limiting their nuclear-related activities.
Nuclear arms control implications
Furthermore, the Russian invasion has impeded near-term opportunities for strategic arms control. Russian and U.S. officials have held no formal arms control discussions since the war began. In late November, the Russian government abruptly canceled a scheduled Russian-U.S. meeting in Cairo to discuss resuming inspections under the New START, which U.S. officials saw as a critical first step toward discussing future measures. The poor performance of Russia’s conventional forces in Ukraine could plausibly elevate Russian interest in non-conventional military capabilities and delivery systems, both for warfighting and as tools of coercion.
The outcome of the Ukraine War might also affect China’s views of nuclear arms control. Chinese leaders might interpret the Ukraine conflict as confirming the importance of having sufficient nuclear forces to negate U.S. deterrence and defense measures protecting Taiwan. Even before the Ukraine conflict, the Chinese government adamantly refused to participate in trilateral strategic arms limitation talks with Russia and the United States or accept other international legal limits on Chinese nuclear forces.
Glimmers of hope
Still, under some scenarios, the Ukraine War might lead Russian and Chinese policymakers to perceive value in pursuing select strategic risk reduction and confidence-building measures with the United States and its allies. These proposals might include making some nuclear weapons activities more transparent or eschewing military operations that threaten civilian nuclear plants in war zones. Additionally, a Ukrainian victory over a nuclear-armed power like Russia could demonstrate to the world that countries do not require nuclear weapons for their defense.