The Bushehr Nuclear Power Plant is home to Iran’s only operational civilian nuclear reactor. In partnership with Russia’s state-owned nuclear conglomerate Rosatom, Iran broke ground for two additional reactors at Bushehr in 2016. Iran claims the area near the plant was attacked four times during the 2026 war in Iran, including one strike in which a projectile hit and killed a security worker. The United States and Israel have not claimed responsibility for the attacks. Photo by Hossein Ostovar / Tasnim News Agency, CC BY 4.0

The Russian state-run nuclear energy company Rosatom evacuated hundreds of workers from the Bushehr nuclear power plant in Iran in late March. The Rosatom employees who remain are responsible for ensuring the safe operation of a nuclear power plant in a war zone—but may also serve the dual purpose of re-affirming Russia’s interests in the region. Long treated as the peaceful counterpart of nuclear weapons, civil nuclear power plants now play a role as a nuclear signaling option in wartime. (Nuclear signaling can be thought of as a non-explicit reminder, at a step below a direct threat, that is meant to call an adversary’s attention to the risk posed by one’s possession of nuclear weapons—though experts disagree on terminology and definitions.)

Russia began its pattern of power plant-based nuclear signaling at Ukraine’s Zaporizhzhia nuclear power plant. There, Russia has deterred Ukrainian forces from retaking the plant by threatening nuclear destruction, potentially leading to nuclear weapons use, should Ukraine and its allies attack Zaporizhzhia. In recent months, Russia has made similar statements about the potential for nuclear catastrophe at the Bushehr plant, as a deterrent to further US strikes.

Although this type of nuclear signaling is likely not a fully developed aspect of state nuclear strategy, Russia has increasingly relied on nuclear power plants as an ad hoc line of defense during wartime. Given Rosatom’s global footprint—Rosatom’s civil nuclear energy projects are expanding across the world, with at least 41 civil nuclear energy projects planned in 11 countries ranging from Bangladesh to Hungary—states must reconsider their nuclear energy contracts with the nationalized energy company. And because there are indications that the United States and Israel may be following Russia’s lead in their recent strikes on Bushehr, the global community must redefine and condemn signaling with nuclear power plants as a new nuclear threat.

Nuclear signaling at Zaporizhzhia. The Russian occupation of Ukraine’s Zaporizhzhia plant—the largest nuclear power plant in Europe—was a watershed moment in nuclear history: the first military occupation of a civilian nuclear power plant. Russia first invaded the Zaporizhzhia power plant in March 2022, and after Rosatom’s efforts to redirect the plant’s electricity from the Ukrainian to Russian energy grids failed, the Russian military repurposed the plant as a military base from which to launch further operations in Eastern Ukraine.

Russia warned that attempts to retake the plant could trigger a nuclear disaster, followed by potential Russian nuclear weapons use. In September 2022, Russian President Vladimir Putin said he was not afraid to use nuclear weapons to protect Russian territory, including the Russian-occupied Zaporizhzhia plant. These statements served as a nuclear deterrent without the deployment of a single warhead—and consequently were less risky for Russia. Although Russia’s occupation of the plant constitutes a serious nuclear, environmental, and humanitarian risk, Russia has attempted to reverse the narrative to signal that a Ukrainian effort to retake the nuclear power plant would be an unjustifiable nuclear risk.

In Ukraine, Russia’s occupation of Zaporizhzhia has become an essential aspect of its nuclear posture, which treats a potential Ukrainian defense of the plant as a nuclear redline. Although Russia has faced international condemnation for its activities in Zaporizhzhia, Russia may view statements about the reactor as less risky and escalatory than those involving weapons capabilities.

Nuclear signaling in the Twelve-Day War. During the Twelve-Day War between Iran and Israel in June 2025, Russia proved itself willing to use similar rhetoric about the potential for civil nuclear disaster. After the United States got involved toward the end of the war and bombed Iranian nuclear enrichment facilities in Isfahan, Natanz, and Fordow, Russia sought to deter further attacks—but without providing political support or military hardware that would detract from its objectives in Ukraine. Russian Foreign Minister Maria Zakharova warned that any US strike on the Bushehr plant “would be an extremely dangerous step with truly unpredictable negative consequences.”

Putin went a step further. When asked how Russia was supporting Iran, Putin implied that continued operation of the Bushehr reactor during the June 2025 war was Russia’s primary means of support for Iran. “Isn’t that support? Iran has not asked us for any other support,” Putin said.

Russia’s approaches in Ukraine and in the Twelve-Day War are not identical, but they both demonstrate a willingness to weaponize civilian nuclear infrastructure through deterring attacks and in service of its strategic objectives.

Iran today: a different geopolitical climate for nuclear energy. In the most recent war in Iran, Russia has so far refrained from making explicit nuclear threats, but the United States and Israel may have adopted a similar ad hoc approach that substitutes threats on civilian nuclear energy infrastructure for traditional nuclear threats. Since mid-March, the United States and Israel have launched four separate strikes that have reportedly hit within the perimeter of the Bushehr nuclear complex. Although the United States and Israel have not claimed responsibility for the strikes—and the projectiles have not hit the reactor or resulted in radiation leaks—the possible targeting of a nuclear power plant is an alarming escalation.

This risk is particularly acute in light of US President Donald Trump’s March 21, 2026, threat to “obliterate their [Iran’s] power plants, starting with the biggest one first.” Some experts have speculated that Trump intended to threaten a strike on Bushehr, which is not Iran’s largest power plant but is the country’s largest nuclear plant. While attacks on civilian energy infrastructure are generally illegal under the Geneva Conventions, a strike on Bushehr would also constitute a risky weaponization with serious nuclear escalation risks beyond those associated with non-nuclear civilian energy infrastructure. Although less thoroughly articulated than Russian threats involving Zaporizhzhia, Trump’s threats suggest that the United States has begun blurring the lines between conventional energy infrastructure, nuclear energy infrastructure, and nuclear weapons.

Rosatom’s reactors worldwide and implications for the global nuclear order. Scholars have begun to identify the new role of nuclear energy infrastructure in war, but what is missing is a serious reckoning with not only the environmental and human effects of attacks on nuclear energy infrastructure but also the ways in which such threats intersect with traditional nuclear signaling. Nuclear energy is not a new wartime technology akin to drones or cyber warfare. Instead, it should be understood as an object of evolving strategic thought. This is not to say that signaling with nuclear power plants isn’t dangerous; to the contrary, it is extraordinarily dangerous. But experts should resist the urge to view nuclear energy and nuclear weapons as distinct threats. The risks of nuclear weapons—physical radiation and uninhibited escalation—can also occur in a world in which nuclear powers see nuclear energy as a platform on which to project their strategic objectives.

This moment not only requires a clear articulation of the risks but also a willingness of all states to reject the use of nuclear energy for wartime signaling. This refusal crucially includes nuclear weapons states but also countries across the world who have increasingly become recipients of Rosatom power plants in what has sometimes been dubbed “the new nuclear age.” As Rosatom’s civil nuclear reactor enterprise expands, Russia’s allies and partners, neutral states, and the global nuclear community must take steps to lessen these risks.

Even for Russian allies and partners like Iran, Rosatom’s nuclear power plants do not serve as a meaningful form of defense but rather as a way for Russia to provide rhetorical—but not tangible—support. For example, Iran has not benefited from Russian signaling as it continues to face devastating losses. Meanwhile Russia has received much-needed financial relief from oil sanctions lifted by the Trump administration. Russia’s allies considering contracts with Rosatom might take the Iranian case as a cautionary tale.

For more neutral states, Russian nuclear infrastructure could serve as a tool of unwanted Russian power. Rosatom is currently building power plants in India and Bangladesh, and has signed memorandums of understanding for nuclear energy deals with Niger, Burkina Faso, and Guinea. The choice to sign with Rosatom offers states a genuine opportunity to construct affordable energy plants, which is often made with an understanding of the technical dependencies that they may generate.

Less understood is the potential that Russia will use these power plants as nuclear signals during conflict. Niger, Burkina Faso, and Guinea are all parties to the Treaty of Pelindaba, which declared the African continent a nuclear-weapon-free zone. States should be aware that nuclear power plants may pose a new risk to their long-held opposition to nuclear war.

Russia’s weaponization of civil nuclear energy infrastructure sets a dangerous precedent that other nuclear weapon states, such as the United States, have seemed to follow. Going forward, all nuclear weapon states must condemn this kind of signaling and refuse to engage in it themselves.

The weaponization of civil nuclear energy infrastructure has negative implications for the Nuclear Non-Proliferation Treaty (NPT) and global nuclear norms. Since 1970, the NPT’s grand bargain has sought to prevent nuclear proliferation by encouraging nuclear disarmament and ensuring support for non-nuclear weapon states to benefit from the peaceful uses of nuclear science. Should the use of civil nuclear energy plants for wartime nuclear signaling expand beyond the small number of existing cases, civil nuclear energy may look like a liability for states instead of a peaceful alternative to proliferation.

Nuclear energy at the 2026 NPT Review Conference. At the ongoing NPT Review Conference, states have already raised the alarm about threats to nuclear energy infrastructure during wartime. The European Union, for instance, urged Russia “to refrain from carrying [out] attacks on such infrastructure, which constitute a serious threat to nuclear safety and security.” The Non-Aligned Movement broadly condemned strikes on nuclear infrastructure. Both statements treated risks at nuclear energy installations as the unfortunate byproduct of careless actions and armed conflict in the vicinity of power plants. But the connection between nuclear energy and nuclear escalation is not accidental; it is the result of an increasingly prevalent nuclear signaling strategy.

During the Cold War, US and international diplomats saw nuclear energy and other civil nuclear technologies as the peaceful partner to nuclear weapons, an assumption embedded in the NPT and other global nuclear treaties. But recent developments raise the possibility that nuclear energy installations will increasingly become flashpoints in war.

Preventing this outcome requires states to hold each other accountable and to forcefully denounce the use of nuclear energy infrastructure in nuclear signaling. At the NPT Review Conference, state parties should, at a minimum, resolve to follow and implement the International Atomic Energy Agency’s Seven Indispensable Pillars for nuclear safety and security in Ukraine, which include resolutions to maintain the physical integrity and backup power supply of nuclear plants.

Ideally, though, states will go further. The international community must reconsider what nuclear signaling entails and refine a broader definition of the nature of nuclear threats in wartime. This will require engagement beyond the ongoing NPT Review Conference and an effort on the part of academics, policy makers, and the public to reconceptualize the many uses and misuses of nuclear power plants.