Israel’s attacks on Iran’s nuclear facilities have used the program’s dispersion to its advantage.
Can Israel destroy Iran’s uranium enrichment facility at Fordow? That question is central to the debate about Israel’s ability to knock out Iran’s nuclear program, and whether the United States should join in.
It turns out that is the wrong question. By striking Iran’s known capacity to complete the nuclear fuel cycle and produce material for an explosive device, Israel has effectively rendered the regime’s most sensitive enrichment facility irrelevant, at least for now. Even if this site remains active, in the absence of Iran’s other nuclear facilities, Israel has already struck; it is no longer the regime’s readiest breakout path to a bomb. The real danger, at least in the near term, is Iran “sneaking out.”
Dug into a mountain near the holy city of Qom, Fordow has become Iran’s one-stop enrichment shop where its best centrifuges make its highest-enriched uranium. At the time Israel’s operation began, perhaps as many as 3,000 centrifuges operated at Fordow, compared to five times as many machines at Iran’s much larger Natanz complex.
But Iran put the vast majority of its best IR-6 centrifuges at Fordow, where they enrich uranium to 60 percent purity—enough for a crude nuclear test device, and fully 95–99 percent of the effort needed to achieve 90 percent purity for a nuclear warhead. And unlike its lines, or cascades, of IR-6s at Natanz, those at Fordow are configured to reach 90 percent enriched uranium in a snap. The site is thus responsible for Iran’s capacity to churn out an arsenal’s worth of weapons-grade uranium nearly overnight.
If Iran were to attempt to produce a nuclear weapon, it is therefore logical that Fordow would have provided the necessary fuel. Tellingly, two years ago, engineers there briefly enriched to 84 percent, roughly the same fissile material level as the Hiroshima bomb.
Iran chose Fordow for such activities precisely because of its design. Referring to the site just days before Israel’s operation, International Atomic Energy Agency (IAEA) Director Rafael Grossi noted the “most sensitive things are half a mile underground [about 800 meters]—I have been there many times,” adding, “to get there you take a spiral tunnel down, down, down.”
Buried deep underground, Fordow is well beyond Israel’s reach. When dropped in succession, Israel’s biggest known bunker busters—2,000-pounders carried by F-15 “bomb trucks”—can drive through an estimated ten-plus feet of concrete or dozens of feet of soil before detonating. Such munitions, used in large numbers, were enough to kill Hezbollah leader Hassan Nasrallah last fall while he sheltered under some 60 feet of concrete.
Yet, this would still be far short of Fordow’s halls that have been drilled under hundreds of feet of solid rock. Only America’s Massive Ordnance Penetrator (MOP), a 30,000-pound behemoth deployed by strategic bombers to neutralize fortified underground strategic sites, is believed to be capable of eliminating Fordow. Israel conspicuously lacks this munition, the platforms to carry it, and any feasible options to acquire these from the United States.
At the same time, Israel’s tactical agility offers potential, though still very challenging, workarounds. David Albright, an expert on Iran’s nuclear program, suggests Israel could at least render the facility unusable, without destroying it, by knocking out aboveground ventilation systems and entry points. As Israel’s ambassador to the United States said recently, “not everything is a matter of, you know, taking to the skies and bombing from afar.”
Indeed, just last year, Israel executed a daring combined-arms assault, including commando raids, to take out an underground missile factory near Masyaf, Syria. Such an operation against Fordow, however, involves significant risks. Although its air assets and air defenses might be inoperable, Iran retains major ground forces that would presumably defend the site.
Fordow’s fortifications, however, were not the only way Iran sought to protect its nuclear setup. Having seen previous Israeli strikes deal major damage to Iraq’s and Syria’s overly centralized above-ground nuclear programs, Iran inferred the importance of dispersal as well as cover. It aimed to complicate military strikes by disaggregating its nuclear fuel cycle across multiple sites. As Grossi put it recently, “one thing is certain, the program runs wide and deep.”
Wide, but most of it is not that deep. Fordow created redundancy in Iran’s enrichment program after it realized the dozens of feet of earth and concrete over its larger Natanz plant were insufficient. The rest of Iran’s uranium production chain lacks any such resilience. The other stages in its nuclear fuel cycle are really chokepoints, and none of them have defenses like Fordow or even Natanz.
At the front end, Iran has multiple uranium ore mines, but only one known site, at Ardakan, where it is milled into yellowcake. This concentrated powder was then transported to Isfahan for conversion into unenriched uranium gas (UF6) and subsequently to Natanz and Fordow for enrichment. Much of the enriched product, in turn, went back to Isfahan for stockpiling. Another facility at Isfahan converted these stocks into enriched uranium metal in preparation for, perhaps one day, machining into specific shapes for an explosive device.
In this way, Iran’s nuclear nodes must work together as a system that requires each, or at least most, elements to function as a whole. Fordow might be the single most important site. Still, its utility is limited since Israel severely degraded or destroyed chokepoints upstream and downstream—namely, the key facilities at both the Natanz and Isfahan complexes.
The ongoing focus on Fordow, instead of the full range of Iran’s nuclear facilities, obscures the fact that Israel has effectively, and unexpectedly, already dealt serious damage to Iran’s nuclear project. They have done this by turning what Iran thought to be one of the strengths of its program—its dispersal—against it. Iran’s nuclear program, it turns out, is just the sum of its parts.
If enough of those parts are damaged or destroyed, even if some facilities survive, the program will be significantly disrupted. Fordow might be untouched, but it is now also isolated—cut off from the facilities that feed its centrifuges and transform its output into usable material for a nuclear weapon. Israel compounded Iran’s problem by frying much of the regime’s nuclear software along with the hardware, as many of its top nuclear scientists and program managers were killed in the opening strikes of the conflict.
This has turned the can-it-or-can’t-it debate about a potential Israeli military strike on its head. To be sure, prewar opponents of an Israeli attack will now point to Israel avoiding the site as vindication. Others already suggest Iran’s nuclear program remains fundamentally intact, and Israel’s mission incomplete. This assessment seems to be bolstered by reports that Israel requested that the United States join its operation specifically to use MOPs against Fordow.
But preventing a nuclear Iran, and gauging the success of Israel’s bold decision, does not hinge on the fate of Fordow itself, at least for now. Important as it will be to destroy Fordow sooner rather than later, most urgently, the United States and Israel must ensure Iran does not sneak out using its undeclared nuclear infrastructure. Alongside depth and dispersal, opacity is the third aspect of Iran’s efforts to make its nuclear program resilient against prevention. It is also the passive defense system least impinged by Israeli action.
Mere hours before Israel hit its first targets in Iran, the IAEA issued a comprehensive catalog of Tehran’s systematic campaign to deceive inspectors about its weaponization progress, including covering up its past assembly of nuclear devices and “cold testing” them with unenriched uranium. Grossi has warned for years that his agency no longer knows where all of Iran’s centrifuges and enriched uranium stocks are kept. Nor can the IAEA confidently say Iran does not have secret sites somewhere in the country.
Perhaps Israel’s ongoing campaign has, or will, neutralize some of these facilities, many of which are interwoven with the IRGC, whose installations are being pounded relentlessly. Even so, leveraging and building upon Israel’s stunning air dominance over much of Iran’s skies is now key to maximizing informational awareness that can detect and deny any Iranian scramble to the finish line. This includes maintaining persistent surveillance and strike capabilities over Fordow to ensure Iran does not attempt to move any highly enriched uranium from that facility to a secret weaponization site, and to interdict any movements if it does.
For now, ideally, Iran will be deterred, given that any movement from Fordow’s handful of fixed and narrow exit points leaves it highly vulnerable. At the same time, regardless of whether the United States undertakes any military operations inside Iran, it should devote significant intelligence resources to monitoring any sneak-out attempts and identifying possible covert facilities.
This does not mean that Israel has achieved its goals, that Fordow can be left unmolested without worry, or that Iran will not strive to reconstitute its nuclear program. To secure these objectives, the United States will need to become more directly involved in what Israel so effectively initiated. But Israel has just shown that to stop the clock on Iran’s nuclear ambitions, for now, it just needed to eliminate some of its parts.
About the Authors: Blaise Misztal and Jonathan Ruhe
Blaise Misztal is the Vice President for Policy at the Jewish Institute for National Security of America (JINSA).
Jonathan Ruhe is the Director of Foreign Policy at JINSA.
Image: ypstudio92 / Shutterstock.com.
