Author: Ms Sanaa Alvira, Research Associate, Centre for Air Power Studies
Keywords: Iranian nuclear programme, nuclear non-proliferation, International Atomic Energy Agency, NPT
On June 21, the United States launched airstrikes against three Iranian nuclear facilities at Fordow, Natanz and Isfahan in an operation codenamed Midnight Hammer. [1] These strikes came amid a series of coordinated Israeli airstrikes on June 12 and 13, codenamed Operation Rising Lion, which targeted key components of Iran’s military and nuclear infrastructure in a bid to stop Iran from developing a nuclear weapon. [2]
While the full extent of the damage remains unclear, satellite imagery shows severe destruction at Natanz, Iran’s largest uranium enrichment facility. Fordow, a heavily fortified underground facility housing advanced centrifuges, was hit by a 30,000-pound bunker-buster bomb dropped by a US B-2 bomber. However, it is unclear whether the facility itself was damaged. Meanwhile, over two dozen Tomahawk cruise missiles, launched from an Ohio-class nuclear submarine in the Gulf of Oman, targeted the Isfahan facility. [3] While it may take many years to understand its full impact, observers note that these airstrikes represent an escalation in what was already a long-simmering regional rivalry and raise broader questions about the future of the global nuclear non-proliferation regime. [4]
The most immediate concern that the international community must urgently grapple with is the status of Iran’s stockpile of about 400 kgs of highly enriched uranium (HEU). The Director General of the International Atomic Energy Agency (IAEA), Rafael Mariano Grossi, when asked about the whereabouts of the uranium, said, “I’m not so sure. In a time of war, all nuclear sites are closed. No inspections, no normal activity can take place”. [5] In the days leading up to the attack, it is possible that Iran may have moved this stockpile of 60 per cent enriched uranium to an undisclosed location. Until the Israeli attacks, IAEA inspectors were conducting “more than one visit a day” to Iranian nuclear sites and had regular access to the material. [6]
Following the attacks, however, the HEU has escaped international oversight, and the IAEA inspectors in Tehran are unable to verify that this material has not been diverted for use in weapons. Apart from the potential to weaponise the missing HEU, there are serious concerns about nuclear security. The inability to account for enriched nuclear material increases the risk of covert stockpiling, theft or diversion. If nuclear material can disappear during a crisis, this erodes confidence in the ability of the non-proliferation regime to monitor and contain proliferation threats.
Beyond the immediate potential weaponisation and nuclear security concerns following the lack of international oversight on Iran’s now-missing HEU, concerns may be raised regarding the undermining of the IAEA safeguards regime. On June 12, 2025, Iran was found to be in non-compliance with its safeguards obligations for the first time in almost 20 years. [7] While non-compliance is indeed a significant concern, it does not automatically imply the existence of a nuclear weapons programme. The IAEA has stated that while it cannot confirm that all of Iran’s nuclear activities are peaceful, it has found no credible evidence of a coordinated nuclear weapons programme. [8] This raises a critical question: is it justifiable to launch military attacks on the nuclear facilities of states that are in safeguards non-compliance?
If a state is found to be in non-compliance, it may be reported to the United Nations (UN) Security Council. The Security Council may then resort to the use of force under Article VII of the UN Charter if peaceful dispute resolution and economic sanctions prove ineffective. Experts suggest that unilateral military action by two states could be viewed as setting a concerning precedent for the non-proliferation regime. [9] For example, Ludovica Castelli writes, “The implicit legitimisation of attacks on military nuclear facilities as a counterproliferation strategy has progressively undermined the integrity of the IAEA’s safeguards system and the NPT”. [10]
Additionally, the strikes are likely to raise fears about nuclear facilities becoming potential targets in the event of a conflict. This could weaken the cooperative foundation of the non-proliferation regime, which depends on countries feeling secure and confident in their right to develop peaceful applications of nuclear energy without the fear of military reprisal.
Less understood are the normative implications of attacking nuclear facilities. The global non-proliferation regime encompasses more than a single treaty, although the Nuclear Non-Proliferation Treaty (NPT) is often cited as the “cornerstone” of this framework. [11] With 191 states as parties to it, it is the most universal treaty in the field of nuclear non-proliferation. It also wields significant normative power, which has been highly formalised within this legal regime. The NPT has come under increased pressure in recent years, and the use of military means to achieve objectives may be viewed by some as adding to this strain. These strains and fractures are reflected most glaringly at the NPT Review Conferences. The last Review Conference, held in 2022, failed to achieve consensus on an outcome document, marking the first time in history that two consecutive Review Conferences (2015 and 2022) have disagreed on an outcome document. [12] Given the current state of affairs, it is possible that the next Review Conference, planned for 2026, will also not be able to agree on a final document.
Iran has already threatened to pull out of the treaty, [13] which would mean that it would be free to engage in nuclear activities without the obligation of international oversight of the IAEA. Iran’s parliament has approved suspending cooperation with the IAEA. [14] These developments will have cascading effects in the region. Saudi Arabia has already stated that it will acquire a nuclear arsenal if Iran does. [15] If Saudi Arabia were to acquire nuclear weapons, it is likely that other countries, both within and beyond the region, would seek to do the same. These developments could further deepen divisions in the international community and weaken the norm against non-proliferation. If diplomacy is perceived as ineffective (even if this may not be the case), the very fabric of the non-proliferation system may erode, encouraging nuclear hedging and thereby raising proliferation risks. It is entirely possible for other countries to draw lessons on the value of and need for nuclear weapons from this conflict. Iran or not, some countries are daydreaming about nuclear weapons again. [16]
A more overarching question is whether military action is effective in stopping nuclear programmes in the first place. Preliminary US intelligence suggests that the recent strikes on Iran’s nuclear sites may have only delayed its programme by a few months. [17] If Iran still retains control over most of its nuclear material, it still has the option to build a weapon. Early assessments indicate strikes may not have been able to halt Iran’s nuclear programme altogether, but they may also have potentially further incentivised the acquisition of the bomb. A fuller assessment may take time, but what seems clear now is that any military action risks not only provoking further proliferation but also undermining the credibility of the international system designed to prevent it.
In an already strained geopolitical environment, the willingness to use or threaten to use force to prevent nuclear proliferation represents a return to the era of military confrontation. The non-proliferation regime has been there and done that before: most notably, in 2003, when North Korea withdrew from the NPT, the US invaded Iraq over suspected weapons of mass destruction (WMDs), Iran was found to be engaging in clandestine nuclear activities and, Libya’s secret nuclear weapons programme was exposed. Despite a challenging year, the nuclear order survived and can do so again. Before military force becomes the default tool for managing nuclear threats, the international community must first explore and exhaust all diplomatic options to prevent a more dangerous and divided nuclear future.
******
CLICK TO VIEW THE PDF
Notes
[1] Ian Parmeter, ” The US Has Entered the Israel-Iran War. Here Are 3 Scenarios for What Might Happen Next,” The Conversation, June 22, 2025, https://theconversation.com/the-us-has-entered-the-israel-iran-war-here-3-scenarios-for-what-might-happen-next-259509. Accessed on June 22, 2025.
[2] Amichai Cohen and Yuval Shany, “A New War or a New Stage in an Ongoing War – Observations on June 13 Israeli Attack against Iran, ” Just Security, June 15, 2025, https://www.justsecurity.org/114641/israel-iran-un-charter-jus-ad-bellum/?utm_source=rss&utm_medium=rss&utm_campaign=israel-iran-un-charter-jus-ad-bellum. Accessed on June 20, 2025.
[3] Mariel Ferragamo, “U.S., Israel Attack Iranian Nuclear Targets – Assessing the Damage,” Council on Foreign Relations, June 25, 2025, https://www.cfr.org/article/us-israel-attack-iranian-nuclear-targets-assessing-damage. Accessed on June 25, 2025.
[4] Brianna Rosen, Tess Bridgeman, and Nima Gerami, “The Day After U.S. Strikes on Iran’s Nuclear Program: A Policy and Legal Assessment,” Just Security, June 22, 2025, https://www.justsecurity.org/115234/policy-legal-iran-nuclear-strikes/. Accessed on June 20, 2025.
[5] Jonathan Tirone and Annmarie Hordern, “UN Says It Has Lost Track of Iran’s Near‑Bomb‑Grade Uranium, ” Bloomberg, June 18, 2025, https://www.bloomberg.com/news/articles/2025-06-18/iran-nuclear-infrastructure-location-of-enriched-uranium-stocks-uncertain?embedded-checkout=true. Accessed on June 20, 2025.
[6] Ibid.
[7] Francois Murphy, “IAEA Board Declares Iran in Breach of Non‑Proliferation Obligations,” Reuters, June 12, 2025, https://www.reuters.com/world/china/iaea-board-declares-iran-breach-non-proliferation-duties-diplomats-say-2025-06-12/. Accessed on June 15, 2025.
[8] Francois Murphy, “UN Nuclear Watchdog Has Limited Oversight in Iran. Here’s Why,” Reuters, June 23, 2025, https://www.reuters.com/world/middle-east/limits-un-nuclear-watchdogs-oversight-iran-2025-06-23/#:~:text=The%20IAEA%20says%20it%20cannot,a%20coordinated%20nuclear%20weapons%20programme. Accessed on June 23, 2025.
[9] Rosen, Bridgeman, and Gerami, “The Day After U.S. Strikes.”
[10] Ludovica Castelli, “How Can We Protect Nuclear Facilities?,” The Loop, European Consortium for Political Research, https://theloop.ecpr.eu/how-can-we-protect-nuclear-facilities/. Accessed on June 24, 2025.
[11] United Nations Office for Disarmament Affairs, “Treaty on the Non‑Proliferation of Nuclear Weapons (NPT),” https://disarmament.unoda.org/wmd/nuclear/npt/. Accessed on June 25, 2025.
[12] Sanaa Alvira, “How to Redefine ‘Success’ in Upcoming Nuclear Nonproliferation Talks,” Bulletin of the Atomic Scientists, July 14, 2023, https://thebulletin.org/2023/07/how-to-redefine-success-in-upcoming-nuclear-nonproliferation-talks/#post-heading. Accessed on June 25, 2025.
[13] Yashraj Sharma, “What Is the NPT, and Why Has Iran Threatened to Pull Out of the Treaty?,” Al Jazeera, June 17, 2025, https://www.aljazeera.com/news/2025/6/17/what-is-the-npt-and-why-has-iran-threatened-to-pull-out-of-the-treaty. Accessed on June 20, 2025.
[14] “Iran’s Parliament Approves Bill on Suspending Cooperation with IAEA,” Reuters, June 25, 2025, https://www.reuters.com/world/middle-east/iran-parliament-approves-bill-suspend-cooperation-with-un-nuclear-watchdog-2025-06-25/. Accessed on June 25, 2025.
[15] Julian Borger, “Crown Prince Confirms Saudi Arabia Will Seek Nuclear Arsenal if Iran Develops One,” The Guardian, September 21, 2023, https://www.theguardian.com/world/2023/sep/21/crown-prince-confirms-saudi-arabia-seek-nuclear-arsenal-iran-develops-one. Accessed on June 25, 2025.
[16] Jon B. Wolfsthal, Hans Kristensen, and Matt Korda, “What’s Making Some Countries Daydream about Nukes Again?, ” Washington Post, June 26, 2025, https://www.washingtonpost.com/opinions/interactive/2025/fas-nuclear-weapon-proliferation-risk/. Accessed on June 26, 2025.
[17] Julian E. Barnes, Helene Cooper, Eric Schmitt, Ronen Bergman, Maggie Haberman, and Jonathan Swan, “Strike Set Back Iran’s Nuclear Program by Only a Few Months, U.S. Report Says,” New York Times, June 24, 2025, https://www.nytimes.com/2025/06/24/us/politics/iran-nuclear-sites.html. Accessed on June 25, 2025.
