More than 15 months into the war, Russian attacks against Ukraine’s nuclear plants have yet to release any radiation. As the likelihood of the Zaporizhzhia nuclear plant reopening quickly declines and Putin’s desire to distract the world from his declining political and military standing increases, some experts fear he may want to induce a radiological release from the plant.
In any case, Putin’s military assaults against the Zaporizhzhia plant have already set a worrying precedent. Last December, NPEC held a wargame, the results of which The Bulletin of Atomic Scientists just published, to examine what might happen in a future Russian invasion of Ukraine. In this reinvasion in 2037, Russia targets power reactors in Ukraine, Poland, and Romania. The United States plans to build scores of new reactors in these countries. What if Russian missiles targeted them in a future war?
NPEC tapped the expertise of Ukrainians, Romanians, NATO officials, Poles, US security experts, and Hill staff to find out. It hosted five sessions over two weeks and ran a three-move wargame.
The game’s play revealed how the uncertainties and dangers of military attacks against nuclear power plants can paralyze decision-making and fundamentally alter the course of wars. The military disruptions these uncertainties introduce may far outstrip the safety issues any reactor radiological release might otherwise present. The game’s play revealed three reasons why.
1. Overseas adversaries can easily target allied or friendly nuclear power plants in ways that the United States and its allies are unprepared for. What was stunning throughout the game’s play was the reluctance of the players—other than those representing Ukraine and Poland—to act even after Russian military assaults were made against nuclear power plant sites in Ukraine and NATO countries. The United States team, for example, waited and then failed to extract US personnel at reactor sites that Russia had hit in Ukraine and that were leaking radiation. Only after Russian missiles had induced a loss of coolant at one of Ukraine’s Khmelnitsky Westinghouse reactors and threatened to do the same to nuclear power reactors in NATO countries did the NATO team take decisive action. This consisted of supplying the targeted plants in Ukraine, Poland, and Romania with active defenses and auxiliary emergency cooling equipment.
In the game, nuclear expert team members gave contradictory advice to each of their teams about how well any of these reactors would fare against aggressive military assaults. This was unexpected but turned out to be significant. Radiological leaks were detected but assessments of these leaks’ implications for public safety were only hastily made after the reactors were hit. These assessments also varied widely and were responded to quite differently by each team. The Ukrainians ordered a massive evacuation after Russia struck one of its reactors; Poland, whose reactor site also was hit but was releasing no radiation, took no public safety steps until they detected a radiation cloud from Ukraine drifting over Polish territory.
Although war planners prefer to devise precise, proportionate diplomatic, political, and military responses, this is difficult to do amid ongoing attacks against nuclear plants. The reason why was made evident in the game: The nuclear experts in the game rendered very different assessments of what was happening and how dangerous the assaults on plants might be to the surrounding population. There was a tendency among NATO members, who wished to stay out of the fight, to downplay the safety implications. It was just the opposite among the countries at greatest risk of being painted with radiation. This suggests that such “differences” in threat perception might not be quickly resolved through some technical nuclear forensic assessments of events. The creation of international norms or nuclear safety zones in war zones, meanwhile, may be desirable but are extremely difficult to attain. As such, the risks and benefits of adding new nuclear plants in high-risk war zones must be reassessed.
2. The hesitation of the United States in responding to military assaults against friendly countries’ reactors can risk near-fatal fracturing of US security alliances. In the game, NATO countries closest to the fighting (e.g., Poland) wanted to join Ukraine in conducting deep strikes into Russia against key staging bases that were launching attacks against Ukraine’s reactors. Initially, some NATO countries were sympathetic to Ukraine striking Russia. All NATO members were concerned that matters might escalate and spill over into NATO territory. As a result, NATO was ready to invoke Article 4 of the NATO treaty, which authorizes NATO members to bring issues of concern to the attention of the organization.
Eager to avoid direct military contact with Russia, however, key members of NATO decided to manage Poland’s desire to back Ukrainian strikes against Russia by invoking Article 5. NATO did this less to support military operations (much less to attack Russia) under Article 5, as to deter any independent action Poland might otherwise take against Russia. In the game, the tactic worked: NATO members, including Poland, were deterred from striking Russia. This tactic, however, failed to deter Kyiv. Ukraine unilaterally struck airbases deep in Russia. This action only further amplified the different concerns of NATO members near the action and those of members located farther back.
Such alliance strains can only be addressed in one of two ways: The reactors either must be defended actively or passively so well that radiological releases and electrical failures appear nearly impossible, or alliance war plans and responses must be devised and agreed to in advance and be sufficiently dramatic to deter such attacks. Neither will be easy. As for developing tailored deterrence strategies, the most relevant analogy here may be “pre-planning” to deal with nuclear weapons attacks—a vexing, dubious undertaking at best.
3. Attempts to settle the question of whether military assaults against nuclear plants constitute war crimes or if subsequent radiological releases qualify such attacks as nuclear weapons use can themselves become significant wartime distractions. In the game, Ukraine insisted that Russia’s attacks against reactors constituted an actionable war crime under Protocol 1 of the Geneva Convention. Ukraine and others also claimed such assaults constituted first use of nuclear weapons.
These claims divided NATO players. They subsequently not only delayed actions critical to waging the war, but also prompted Ukraine to act unilaterally in an escalatory action, firing missiles deep into Russia without NATO’s support. This is worth avoiding. Both NATO members (except the United States) and Russia have ratified Protocol 1 of the Geneva Convention, which specifically discourages assaulting nuclear power generating stations. Yet current US legal guidance regarding Protocol 1 is murky. Although the United States is obligated as a signatory to Protocol 1 to avoid attacking nuclear power reactors, Pentagon lawyers insist US commanders should ultimately be free to attack these plants if they think it is necessary. It would be helpful if the US view was clarified and brought into line with the strong presumption of US allies against making such attacks.
Yet another divisive issue is what constitutes first nuclear use. In the game, European NATO members sympathized with Ukraine’s contention that Russia’s “intentional” attacks against nuclear plants that consequently released radiation should be considered a “use” of nuclear weapons. The United States ignored this assertion. Yet another unresolved legal question is whether or not radiation that contaminates NATO soil from an intentional Russian attack of Ukrainian reactors should constitute an actual attack on NATO and, therefore, demand an Article 5 response. The players were briefed on this point but chose not to play it. Here, again, some European NATO public officials have supported the idea, whereas the United States has taken no position.
Prescription for Military Paralysis: Wartime Reactor Meltdowns
After-action Report
For more than a year, nuclear experts have wrung their hands about the risk of radiological releases from the Zaporizhzhia nuclear power plant in southeastern Ukraine and how best to prevent them. More than 15 months into the war, though, Russian attacks against Ukraine’s nuclear plants have released no radiation. This may be no accident. So far, Russian President Vladimir Putin has avoided destroying Ukraine’s nuclear power plants. Otherwise, they would have been demolished long ago. Instead, Putin has aimed to damage them and Ukraine’s electrical supply system as part of a larger effort to erode Ukrainian morale.
His strategy is unlikely to be a one-off. North Korea and China also have “wayward provinces”—South Korea and Taiwan, respectively. And they have long-range missiles too. Beijing and Pyongyang have considered targeting reactors. How these countries might, if at all, follow Russia’s example depends on what they make of Putin’s current assaults against reactor sites.
Reactors in Warzones:
When he launched his full-scale invasion on February 24, 2022, Putin hoped Ukraine would immediately surrender. His initial aim wasn’t to disable Ukraine’s reactors or electrical supply systems but to seize them. And he did: On the first day of the invasion, Russian forces took control of the Chernobyl nuclear plant, and in early March they seized the Zaporizhzhia nuclear plant. Russia’s invasion, however, quickly stalled. As a result, Putin changed his strategy: He directed his military to shell the plant sites and electrical power nodes critical to powering the plants’ coolant pumps and safety equipment. Russian agents also kidnapped and terrorized plant workers, which jeopardized Zaporizhzhia’s safe operation. In addition, Putin stepped-up attacks on the rest of the Ukraine’s electrical supply system to frighten the Ukrainian population further, undermine its will to resist, and possibly destabilize the entire grid, including the nuclear portions of the electrical supply system. So far, these efforts have had mixed results: Some senior officials in NATO countries have been rattled (fearing radiation leaks and military escalation); the Ukrainians, however, have not.
Certainly, Russia’s willingness to take advantage of the military vulnerabilities of nuclear sites in Ukraine has set a precedent. It is unclear if any other nation would make the mistake Russia did in assuming that it could easily seize and hold an adversary’s nuclear facilities at the very outset of hostilities. If not, they might move to Russia’s second stratagem of militarily holding the electrical supply system and its nuclear plants at risk right away. How might such a war proceed? Might Russia aim to knock out the grid, strike Ukrainian nuclear plants, and risk major radiological releases? Might it target NATO reactors (which could include more than 50 US-promised plants in Poland, Romania, and Ukraine by 2037)? How might Ukraine, the United States, and NATO members respond?
To answer these questions, the Washington-based Nonproliferation Policy Education Center (NPEC) designed and hosted a wargame. The game assumed Russia will re-invade Ukraine 15 years from now—in 2037—when both sides will have substantial numbers of long-range, accurate missiles and drones. It also assumed Ukraine and Eastern NATO countries will have new reactors of US design on their territory. In November and December of 2022, NATO officials, American hawks, American doves, Ukrainians, Romanians, nuclear experts, US military officials, and Polish experts were all tapped to prepare, critique, and play remotely over a two-week period.
The game’s play revealed how the uncertainties and dangers of military attacks against nuclear power plants can paralyze decision-making and fundamentally alter the course of wars. The military disruptions these uncertainties introduce may far outstrip the safety issues any reactor radiological release might otherwise present. The game’s play revealed three reasons why.
The US and Its Allies Are Unprepared:
Overseas adversaries can easily target allied or friendly nuclear power plants in ways that the United States and its allies are unprepared for. What was stunning throughout the game’s play was the reluctance of the players—other than those representing Ukraine and Poland—to act even after Russian military assaults were made against nuclear power plant sites in Ukraine and NATO countries. The United States team, for example, waited and then failed to extract US personnel at reactor sites that Russia had hit in Ukraine and that were leaking radiation. Only after Russian missiles had induced a loss of coolant at one of Ukraine’s Khmelnitsky Westinghouse reactors and threatened to do the same to nuclear power reactors in NATO countries did the NATO team take decisive action. This consisted of supplying the targeted plants in Ukraine, Poland, and Romania with active defenses and auxiliary emergency cooling equipment.
In the game, nuclear expert team members gave contradictory advice to each of their teams about how well any of these reactors would fare against aggressive military assaults. This was unexpected but turned out to be significant. Radiological leaks were detected but assessments of these leaks’ implications for public safety were only hastily made after the reactors were hit. These assessments also varied widely and were responded to quite differently by each team. The Ukrainians ordered a massive evacuation after Russia struck one of its reactors; Poland, whose reactor site also was hit but was releasing no radiation, took no public safety steps until they detected a radiation cloud from Ukraine drifting over Polish territory.
Although war planners prefer to devise precise, proportionate diplomatic, political, and military responses, this is difficult to do amid ongoing attacks against nuclear plants. The reason why was made evident in the game: The nuclear experts in the game rendered very different assessments of what was happening and how dangerous the assaults on plants might be to the surrounding population. There was a tendency among NATO members, who wished to stay out of the fight, to downplay the safety implications. It was just the opposite among the countries at greatest risk of being painted with radiation. This suggests that such “differences” in threat perception might not be quickly resolved through some technical nuclear forensic assessments of events. The creation of international norms or nuclear safety zones in war zones, meanwhile, may be desirable but are extremely difficult to attain. As such, the risks and benefits of adding new nuclear plants in high-risk war zones must be reassessed.
To view the full occasional paper click here.