Iran’s Nuclear Sites Hobbled But Not Destroyed, Experts Say

The full extent of the destruction caused by the ongoing missile barrage is only starting to become clear. International Atomic Energy Agency Director General Rafael Mariano Grossi told the United Nations Security Council on Friday that while Israel destroyed surface facilities at Iran’s main nuclear-fuel site in Natanz, it hadn’t yet breached the primary underground halls where uranium enrichment takes place.

Natanz is a critical part of Iran’s atomic program, but results from strikes on other sites — at Isfahan and Fordow — will weigh heavily on Israel’s next moves. 

The risk for Netanyahu is that extending the military campaign could drive the Islamic Republic’s nuclear activities deeper underground, ending access to UN-backed inspectors and potentially hardening Tehran’s resolve. Iran responded to the attacks by targeting Israeli cities with hundreds of ballistic missiles and drones from Friday evening.

Successfully knocking out the Isfahan site would be significant because it’s Iran’s only site for converting uranium into the feedstock used by centrifuges, which in turn separate the uranium isotopes needed for nuclear power or bombs. 

Without capacity to convert new volumes of raw uranium, Iran’s ability to produce additional quantities of enriched product would be frozen. While Iran has ample stockpiles of existing material, its ability to scale up would be limited.

“If you interrupt that piece of the flow-sheet, the fuel cycle doesn’t work anymore,” said Robert Kelley, a US nuclear engineer who led inspections for the IAEA in Iraq and Libya. “The front end of their program dies.”

Israel’s leaders will sift through the damage reports in coming days and decide whether to press ahead with the strikes. The campaign, a long-promised fulfillment of Netanyahu’s promise to target the nuclear program, also killed nine leading scientists whose expertise was crucial for Iran’s nuclear ambitions.

The move has cast doubt about the future of talks between the US and Iran about a diplomatic solution to limit Tehran’s atomic activities in exchange for sanctions relief. A sixth round of negotiations was scheduled to take place on Sunday, but it’s unclear if they will go ahead. 

“There’s obviously not yet a full assessment,” said Suzanne Maloney, a vice president at the Washington-based Brookings Institution. But the combination of strikes and the killing of key security and nuclear personnel is “going to make it very difficult for Iran to reconstitute the program to the level that it was at prior to these attacks,” she said.

Experts said the airstrikes will make it harder to monitor Iran’s atomic activities, given UN-backed inspectors probably won’t be given access to sites for a long time. The attack is also unlikely to end Tehran’s nuclear program even if progress is slowed, according to Kelsey Davenport, director for nonproliferation policy at the Arms Control Association.

“There’s a real risk that Iran may divert uranium, enriched to near-weapons grade levels, to a covert location, or that due to the damage, the IAEA may not be able to account for all of Iran’s nuclear materials,” Davenport said. 

Iran’s 400 kilograms (880 pounds) of highly-enriched uranium could fit in three or four easily-concealed cylinders, according to Robert Kelley, the nuclear-weapons engineer. Concern has mounted that Iran could use the material as the feedstock for a weapon, should it follow-through on threats to opt out of the Non-Proliferation Treaty — a global initiative to prevent the spread of nuclear weapons — and kick out inspectors. 

Another issue is the enrichment site at Fordow, which is buried under a mountain and seen as vulnerable only to the sort of massive bunker-buster bombs that the US alone has in its arsenal.

“Israel cannot destroy Fordow without US military assistance,” Davenport said. 

That leads to the question of whether the administration of US President Donald Trump would join the battle to take out that site. It would be a difficult choice for the American leader, who campaigned on the idea of being a peaceful president and has repeatedly stated he favors a diplomatic solution to Iran’s nuclear issue. 

“Unlike Israel, the United States has bases near Iran, and it could conduct more devastating strikes on nuclear-related facilities as well as degrade Iranian air defenses severely,” the Center for Strategic and International Studies said in a note. “Although the Trump administration might not want to attack Iran, it might feel that doing so is better than allowing Iran to rebuild its nuclear program.”

It was a conundrum that even Israeli officials acknowledged could not be resolved via bombing. National Security Adviser Tzachi Hanegbi acknowledged as much Friday, saying it was “impossible to destroy the nuclear program with force alone.” 

“The goal is to make the Iranians understand that they will have to stop the nuclear program,” Hanegbi told broadcaster Channel 12.

–With assistance from Courtney McBride and Ryan Chua.

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