As the UN Security Council debates the snapback mechanism on Iran, we aim to analyze the US and Israeli military strikes on Iranian nuclear sites in June to demonstrate that both diplomatic pressure and military action inflict only limited damage, while risking to undermine diplomatic momentum for a long time and alienating the world from the shared goals of nuclear nonproliferation.
Background
In June 2025, the United States conducted a major airstrike operation against Iran’s nuclear infrastructure. The operation, codenamed Operation Midnight Hammer, was conducted in coordination with Israel following a series of Israeli strikes and Iranian retaliatory actions. The stated objective was to cripple Iran’s capability to develop nuclear weapons, a claim that has since been subject to scrutiny and debate.
On June 22, 2025, the United States launched a large-scale military strike targeting three major Iranian nuclear facilities located in Fordow, Natanz, and Isfahan near Tehran. The operation involved over 125 aircraft, including seven B-2 Spirit stealth bombers that dropped 14 GBU-57 Massive Ordnance Penetrator bunker buster bombs, as well as Tomahawk cruise missiles launched from a guided missile submarine. The main strikes occurred between 2:10 and 2:35 a.m. local time, with the B-2 bombers focusing on the underground Fordow Fuel Enrichment Plant and the uranium-enrichment facility at Natanz, while the Tomahawks targeted the uranium-conversion facility in Isfahan. The following day, on June 23, Iran retaliated by firing missiles at the U.S. Al Udeid Air Base in Qatar, causing limited damage. A ceasefire was announced on June 24, although both sides accused each other of violations. The Islamic Revolutionary Guard Corps (IRGC) launched a final salvo of 14 missiles targeting Israeli military sites just minutes before the ceasefire officially began, citing it as retaliation for Israeli strikes. Although there were many breaches during the ceasefire from the Iranian or Israeli sides, there were no further US-Israeli strikes on the Iranian nuclear facilities after June 24.
Timeline of US-Israeli Attacks on the Iranian Nuclear Sites
Date of an event
Event
Alleged weapons used
Targets
Alleged damage
June 13-24, 2025
Israel launches Operation Rising Lion ( five waves of airstrikes
200 fighter jets, dropping over 330 munitions
Tehran, Fordow, Natanz, Evin Prison, IRGC command centers, and other regions
– Limited damage made to Fordow Fuel Enrichment Plant, – Two buildings damaged at Iran Centrifuge Technology Company (TESA) in Karaj – Tehran Nuclear Research Center (TNRC) was damaged – Two buildings at Shahid Meisami Group complex in Karaj, which produces chemical weapons, destroyed – The IR-40 reactor containment building was destroyed by a direct hit on 19 June, as were distillation towers at the adjacent heavy water production plant
The US attacks primarily targeted three key Iranian facilities: Fordow, Natanz, and Isfahan, aiming to inflict significant damage to sites critical for Iran’s uranium production capabilities. The operation was publicly declared a success. However, emerging evidence suggests that the actual impact may have been more limited than initially claimed. This paper will closely examine the strikes on these facilities and evaluate the true extent of the damage in comparison to the official statements.
Composition of the US strikes
Site
Munition Type
Quantity
Mass per Unit (kg)
Explosive power
Total Mass (kg)
Natanz
MOP (GBU-57)
2
13,607
2400- 2600 kg
27,214
Fordow
MOP (GBU-57)
12
13,607
2400- 2600 kg
163,284
Isfahan
Tomahawk
30
450
2, 600 kg
13,500
Total
206,186
This amounts to approximately 206.2 metric tons of ordnance delivered
Fordow underground complex: overview
The Fordow underground complex, officially known as the Shahid Ali Mohammadi Nuclear Facility, is a highly fortified uranium enrichment plant located near the city of Qom, Iran. Originally constructed as an Islamic Revolutionary Guard Corps military base, Fordow was later converted into a nuclear site and became operational in 2009. Its primary function is uranium enrichment, and it is regarded as Iran’s most secure nuclear facility, being buried approximately 80 to 110 meters beneath a mountain to withstand potential airstrikes.
The facility was designed to house thousands of centrifuges, initially for the enrichment of uranium up to 5% for fuel purposes, but later adapted for higher enrichment levels. Under the 2015 Joint Comprehensive Plan of Action (JCPOA), Iran was prohibited from enriching uranium at Fordow for 15 years and was required to convert the site into a research center. However, following the U.S. withdrawal from the JCPOA, Iran resumed enrichment at Fordow, including the production of uranium enriched up to 60%.
There are several types of centrifuges used for uranium enrichment, with the most prevalent being the gas centrifugeand the Zippe-type centrifuge. Both types operate in large arrays called cascades, where the output of one centrifuge feeds into the next to achieve higher enrichment levels. While older methods like gaseous diffusion have been largely phased out due to high energy consumption, centrifuge technology dominates modern uranium enrichment because it is much more energy efficient and cost-effective.
Before the strike the Fordow facility was spotted to have several Iranian trucks that were reportedly either fortifying the nuclear sites or displacing the HEU.
The US attack: reported and estimated damage
According to a press conference by Defense Secretary Pete Hegseth and Air Force General Dan Caine, Chairman of the Joint Chiefs of Staff, the United States dropped 12 bombs on the Fordow facility. Satellite imagery reveals a total of six craters, indicating that the strikes were concentrated on the mountain directly above the underground centrifuge halls, with little to no visible damage to above-ground infrastructure. General Caine explained that all 12 missiles were aimed at these hardened underground targets.
While U.S. officials described the operation as a success, there is no independent confirmation of the actual impact, as Iran has since restricted the International Atomic Energy Agency (IAEA) from accessing its nuclear facilities. As a result, the true extent of the damage remains unknown.
To assess the likely outcome of the strike, several quantitative methods can be applied. One of the most reliable is the penetration equation developed by Sandia National Laboratories, which allows for an estimation of depth achieved by earth-penetrating weapons using key physical and geometric parameters. In metric form, this equation provides a useful framework for estimating how far each munition could penetrate into reinforced rock or concrete.
Dkinetic=C*S*N*(W/A)0.7⋅(V−30.48), where:
· D = penetration depth (m)
· C = empirically calibrated constant (≈ 0.0565 for metric units)
· S = target strength factor (empirical; ~0.76 for reinforced rock)
· N = nose coefficient (≈ 0.85 for ogive-nose penetrators)
· W = penetrator mass (kg)
· A = cross-sectional area (m²)
· V = impact velocity (m/s)
· V0 = threshold velocity (≈ 30.48 m/s)
We know the velocity, cross sectional area and weight from the open source: For GBU-57: W=13,607 kg, A=0.503 m2, V=440 m/s.
The variables for the solid rock targets are taken from the National Academy research paper on the Earth-Penetrator Weapons.
Thus, the calculation will be: D=0.0565*0.76*0.85*(13.607/0.503)0.7*(440−30.48) = 18,927 meters.
This equation allows estimate only a kinetic penetration, but doesn’t take into account the explosive power which is: Dexplosive≈k*W1/3
Dexplosive= crater depth caused by explosive (m)
W = TNT equivalent (kg)
k = material-dependent constant (typically ~0.6–1.2 for soil, 0.2–0.4 for concrete)
Thus, Dexplosive ≈ 0.3*27001/3≈0.3⋅14=4.2 m
The D1 total≈ Dexplosive+ Dkinetic ≈ 18,927 + 4.2m ≈23,127 m
To estimate the effects of multiple strikes, we adapt the model by progressively reducing the effective target strength in each subsequent strike to reflect the cumulative fracturing and weakening of the material caused by prior impacts. This is based on physical testing and modeling insights presented in National Academies reports, which recognize that repeated kinetic and explosive loading can significantly degrade the structural integrity of rock or reinforced concrete. For the second and third strikes, the target strength coefficient S is reduced to reflect this degradation, for example, from 100% in the first strike to 60% and then 40% in later strikes.
Thus, assuming there were three strikes for one or two targets the D2total ≈25–28m, D3total ≈ 30–35m. The total penetration depth thus might have reached Dtotal=D1+D2+D3≈22.6+27+33=82.6m. However, this figure is likely to be exaggerated, since the equation is based on idealized conditions,uniform, unfractured material, optimal impact angle, and no consideration of target reinforcement complexity or layered geology. Moreover, this estimate assumes that at least one target was struck by three missiles – a scenario that has not been confirmed. Therefore, while it is possible that the strikes reached the underground hall, there is no definitive evidence that the underground complex was penetrated. However, the shockwaves from the impacts may have caused some structural damage to the facility.
Before the US attack
After the US attack
Reactions of the Iranian officials and the IAEA
Manan Raeisi, a lawmaker representing the city of Qom, near Fordow, said the damage from the attack was “quite superficial.” The IAEA didn’t have access to the facilities and couldn’t assess the damage made to the underground complex. However, IAEA Director General Rafael Grossi said that “one cannot exclude (the possibility) that there is significant damage there.” A day later, in a statement to the IAEA’s board of governors, Grossi’s language sharpened. “Given the explosive payload utilized, and the extreme(ly) vibration-sensitive nature of centrifuges, very significant damage is expected to have occurred.”
Conclusion:
While the probability of the strikes reaching the underground hall is high, it cannot be stated with certainty that penetration into the hall was achieved.
Strikes on Natanz
The US also targeted Natanz in its Saturday night operation. A US official said a B-2 bomber had dropped two bunker-busting bombs on the site. US Navy submarines also fired 30 TLAM cruise missiles at Natanz and Isfahan. A CNN analysis of satellite imagery showed two new craters had emerged at the site, likely caused by the bunker-busting bombs. The craters – one with a diameter of around 5.5 meters, the other around 3.2 meters, according to the Maxar images – sit directly above parts of the complex located underground.
Given that the Natanz complex is located approximately 80 to 90 meters underground and only two bombs were dropped on separate targets, the likelihood of those strikes reaching the underground facility is low. The weapons used were the same GBU-57s as in the Fordow operation, with an estimated maximum penetration depth of around 22 meters.
Moreover, during the press conference, U.S. officials provided few details about the strike on Natanz and did not comment separately on the outcome of that specific operation. Strikes on
Strikes onIsfahan
Isfahan Nuclear Technology Center was one of the targets that Israel struck on June 13, 2025, prior to the U.S. involvement in the conflict. In that initial wave of operations, the Israeli Air Force, employing nearly 50 F‑35I and other combat jets, dropped approximately 150 precision munitions. Following the Israeli strikes, the US laucnhed Tomahawk strikes on the facility on June 22. Satellite imagery confirms widespread destruction across the conversion plant, which was the main target in this operation, including the near-total demolition of the main uranium conversion building, previously identified by experts.
The strikes targeted key infrastructure at the Isfahan Nuclear Technology Center, including its uranium conversion facility, and the Uranium Metal Conversion Plant at the ENTC, which Iran could have used to transform uranium gas into dense metal in a process called metallization. Besides, the strikes damaged the Tehran Reactor Fuel Manufacturing Plan (FPFP) and the Central Chemical Laboratory. The FPFP produces natural uranium metal and stored approximately 85 percent of Iran’s 20 percent enriched uranium stockpile and 83 percent of Iran’s 60 percent enriched uranium stockpile as of August 2023. It is unclear how much, if any, of Iran’s enriched uranium stockpile was at FPFP at the time of US and Israeli strikes. However, as the Institute of the Study of War notes that even if there was enriched uranium at the plant, the US and Israeli airstrikes on ENTC and other enrichment facilities could have buried enriched uranium underground, which would limit access to the material, but could not have destroyed the material.
As of the latest publicly available information, the Uranium Conversion Facility located at the Isfahan Nuclear Technology Center is the Iranian only uranium conversion facility. The site is used for converting uranium oxide (“yellowcake”) into uranium hexafluoride (UF₆) and uranium dioxide (UO₂), both essential feedstocks for enrichment process. As the conversion plant is an onground facility the massive destructive effect caused by the strikes is undeniable.
U.S. Secretary of State Marco Rubio referenced the strike’s success, suggesting the conversion facility had been completely eliminated. Intelligence agencies, media and independent nuclear experts suggest it will require “many months” for Iran to restore at least partial functionality of the site. Full reconstruction and a return to pre-strike production levels could take multiple years, especially given the need to replace sensitive chemical processing systems, source hard-to-obtain components, and potentially decontaminate parts of the site.
Thus, the U.S. and Israeli strikes on Iran’s Isfahan facility severely damaged its uranium conversion capabilities, disrupting the production of uranium hexafluoride necessary for enrichment, while Iran’s existing stockpile of enriched uranium remained largely unaffected.
Iranian officials targeted during the operation
During the US and Israeli airstrikes on Iran from June 12 to 24, several high-ranking Iranian military and security officials were killed, significantly impacting Iran’s command structure. Israeli forces confirmed the deaths of several senior military officials as well as 56 Artesh personnel,16 conscript soldiers, nuclear scientists linked to Iran’s weaponization efforts.
General Ali Hossein Mohammadi, 71st Mechanized Infantry Brigade commander
General Ali Piri, senior Air Defense Force officer
General Gholam Ali Najafi, senior Air Defense Force officer
Mohammad Bagheri, the chief of staff of the Iranian armed forces
Hossein Salami, commander of the IRGC
Amir Ali Hajizadeh, commander of the IRGC Air Force
Brigadier General Mehdi Nemati, deputy director of the Law Enforcement Command Intelligence Organization and a veteran who fought alongside the late Qassem Soleimani, was also killed.
Key takeaways
– The recent strikes on Iranian nuclear facilities have caused varying levels of damage across multiple sites. At the Fordow Fuel Enrichment Plant, twelve bombs were dropped on the underground complex, resulting in limited damage; although some damage is likely due to the attack, the heavily fortified nature of the facility means the destruction is not severe. In Karaj, two buildings at the Iran Centrifuge Technology Company (TESA), which manufactures centrifuge components, were destroyed.
– Additionally, the Tehran Nuclear Research Center (TNRC) sustained damage to one of its buildings, affecting centrifuge rotor manufacturing and testing. Another critical hit in Karaj involved the destruction of two buildings at the Shahid Meisami Group complex, which is linked to chemical weapons production. A significant blow was dealt to the IR-40 heavy water reactor when its containment building was destroyed by a direct hit on June 19, along with damage to the distillation towers at the adjacent heavy water production plant. In Isfahan, the Uranium Metal Conversion Plant was nearly destroyed, while the Conversion Plant itself and the Tehran Reactor Fuel Manufacturing Plant were also damaged. Thus, significant damage to Iranian research centers, heavy water facilities, and related infrastructure is undeniable.
– However, when it comes to the underground sites,which are far more critical to uranium production,the damage is assessed to be limited. At Natanz, two bombs struck the underground uranium enrichment complex, but no significant structural damage was reported; however, the above-ground facilities, including the Pilot Enrichment Plant and key electrical infrastructure, were destroyed, likely rendering the centrifuges inoperable. Furthermore, the metal conversion facility at Natanz was severely damaged.
– Beyond the nuclear sites, the strikes also caused significant damage to Iran’s strategic command infrastructure as part of the larger military offensive.
– In the long run, the strikes undermined any prospects for trust-based negotiations between Iran and the West. They also damaged Iran’s confidence in the IAEA, which appeared very inactive in response, providing Iran with a pretext to accuse the Agency of bias and announce a suspension of cooperation. Ultimately, the strikes deepened the polarization between Iran and the West, with one side openly applying pressure, as seen now in the snapback discussions, and the other withdrawing from any cooperative efforts.
References:
Effects of Nuclear Earth-Penetrator and Other Weapons, 2005. National Academies Press, Washington, D.C. https://doi.org/10.17226/11282
