Iran’s ability to produce sufficient highly enriched uranium for an atomic weapon has been set back by several months to several years following a large blast at one of its central nuclear facilities earlier this month, which has widely been attributed to Israel, according to a US-based defense analyst.
Simon Henderson, of the Washington Institute for Near East Policy think tank, said the alleged attack targeted an above-ground centrifuge assembly plant at the otherwise subterranean — and thus hard to attack — Natanz uranium enrichment facility.
Henderson, writing on The Hill website this week, also warned that Iran may retaliate for the alleged assault on its nuclear program with an attack on Israel’s nuclear program.
“The danger is that Tehran will think in terms of a ‘nuclear’ response — an attack targeting an Israeli nuclear facility such as the Dimona research reactor in southern Israel,” he wrote.
Last week, Israel’s Channel 13 reported that the country was bracing for a potential retaliation for the blast at Natanz, as well as a series of other mysterious explosions and fires at facilities throughout Iran, which many have speculated were caused by the Jewish state. Earlier this week, Channel 12 also reported that the Mossad spy agency had recently foiled planned or attempted Iranian attacks on Israeli diplomatic missions in Europe and elsewhere that were apparently in response to these incidents.
Israeli officials have largely refrained from commenting on the incidents. On Sunday, Defense Minister Benny Gantz responded to a question about the matter in an Israel Radio interview, saying only that “not every event that happens in Iran is connected to us.”
Henderson said Israel likely believed that Iran was restarting production of the powerful centrifuges needed to enrich sufficient quantities of uranium to manufacture a nuclear weapon.
Centrifuges work by spinning incredibly quickly — tens of thousands of rotations per minute — which separates out the contents inside by weight. In the case of uranium, this means that the lighter uranium-235, which can be used in nuclear fission reactions, is separated from the heavier uranium-238, which can’t.
Currently, Iran mostly possesses less advanced IR-1 type centrifuges, but these are not capable of enriching uranium to the level needed for a bomb. As many of its next-generation IR-2m centrifuges, which are capable of enriching uranium to weapons-grade levels, were turned offline as part of the 2015 nuclear deal, known as the Joint Comprehensive Plan of Action, and have likely become unusable in the intervening years, Iran would have needed to get these machines back up and running in order to continue its alleged push to a bomb.
Under the JCPOA, Iran was permitted to continue its nuclear program but only with civilian projects and with caps on the levels of enrichment and quantities of enriched uranium that it was allowed to possess. In 2018, US President Donald Trump abandoned the deal and put in place fresh economic sanctions, prompting Iran to retaliate by enriching uranium to greater levels and stockpiling more of it than the agreement permitted.
“The assumption is that Iran has restarted large-scale production of the IR-2m centrifuges — or at least it had until last week,” Henderson wrote.
Once assembled, the new centrifuges would actually operate at the Natanz facility far below ground, buried deep under concrete and steel, which would make them incredibly difficult to target with a bomb. However, they were vulnerable while they were still being put together in the above-ground building that was targeted. In 2010, the United States and Israel reportedly targeted Iranian centrifuges at Natanz with a cyberattack known as Stuxnet, which caused some of them to spin incorrectly and eventually tear themselves apart.
According to Henderson, an expert in energy policy, the Natanz centrifuge assembly plant was likely Iran’s only facility capable of producing the more advanced IR-2m models.
“Therefore, production of IR-2ms has stopped and, from Israel’s point of view, the likelihood of Iran obtaining enough highly-enriched uranium for its first nuclear weapon has been delayed by months, perhaps even years,” he wrote.
Iranian officials have regularly claimed that they do not seek a nuclear weapon; however these claims have largely been discounted and discredited by Tehran’s enrichment of uranium to levels beyond those needed for civilian technology, as well as by Iranian documents — stolen by Mossad in 2018 — that showed plans to connect a nuclear weapon to a missile.
On Tuesday, Nour News, an Iranian website close to the country’s Supreme Council of National Security, said the building at Natanz was damaged in “a deliberate attack,” in the first apparent public acknowledgment from Tehran that the incident was not an accident.
The precise method used to attack the centrifuge assembly site is not yet known, bot an unnamed Middle East intelligence official told The New York Times that a powerful bomb was used, and that Israel was behind the blast. A member of Iran’s Islamic Revolutionary Guard Corps also told the newspaper that a large explosive caused the damage.
Iran admitted Sunday that Natanz incurred “considerable” damage from the explosion, as satellite pictures appeared to show widespread devastation at the sensitive facility. It had previously sought to downplay the damage from the blaze, releasing only one image of the site showing a small number of scorch marks, but the emergence of satellite images showing far more destruction effectively forced Tehran to acknowledge the scope of the blast.
The building was constructed in 2013 for the development of advanced centrifuges, though work was halted there in 2015 under the nuclear deal with world powers, Iran’s atomic agency spokesman Behrouz Kamalvandi said earlier this week.
When the United States withdrew from the nuclear deal, the work there was renewed, Kamalvandi said.
The Associated Press contributed to this report.