Natanz: What Remains in the Shadows

The strikes against Iran’s nuclear facilities demonstrated the intelligence and military capabilities of Israel and the United States. But the ultimate strategic test is not simply what was destroyed. It is what remains, and how reliably that can be determined.

In June 2025, Israel demonstrated that even one of Iran’s most heavily protected nuclear facilities was not beyond its reach. Natanz, a focal point of the covert campaign against Iran’s nuclear program for more than two decades, sustained extensive damage. Critical infrastructure was destroyed, enrichment systems were disrupted, and capabilities that had taken years to develop were severely impaired.

Yet sixteen months later, a crucial question remains without a complete, independently verified public answer: What nuclear capabilities does Iran still possess, where is the material that survived the strikes, and how quickly could Tehran restore its enrichment operations?

These questions do not diminish the military and intelligence achievements. They highlight the distinction between operational success and a lasting strategic outcome.

Destroying a nuclear facility is an achievement that can be documented. Preventing an adversary from rebuilding its capabilities is a far more complex undertaking.

The history of Natanz illustrates that distinction.

Revealed publicly in 2002, Natanz developed into one of the principal centers of Iran’s nuclear program, housing thousands of centrifuges and underground enrichment facilities. For Tehran, it represented technological independence. For Israel and Western governments, it raised a fundamental concern: that advanced uranium enrichment capabilities could bring Iran closer to acquiring nuclear weapons.

Iran has consistently maintained that its nuclear program is peaceful. Israel and other countries have pointed to Iran’s history of undeclared nuclear activities, elevated enrichment levels, and restrictions on international inspections as grounds for serious concern.
The central issue was never solely what Iran was doing at a particular moment, but what it might become capable of doing if its leadership changed course.

The confrontation was not fought exclusively with aircraft and bombs. For years, it involved intelligence collection, monitoring of procurement networks, cyber operations, and covert activities attributed in public reporting to Israel and the United States.
The discovery of Stuxnet in 2010 marked a turning point. Widely attributed to a joint American-Israeli operation, the computer worm interfered with the industrial control systems operating Iranian centrifuges. It demonstrated how intelligence, technological expertise, and cyber capabilities could disrupt critical infrastructure without an overt military strike.

In July 2020, an explosion damaged a centrifuge assembly facility at Natanz. In April 2021, a major disruption to the site’s electrical system was described by Iranian authorities as sabotage. Israel was suspected of involvement, although responsibility for individual incidents and their operational details were not fully confirmed publicly.

These operations illustrated both the potential and the limits of covert disruption.
Damaged centrifuges can be replaced. Destroyed installations can be rebuilt. Scientific knowledge and engineering expertise do not disappear when buildings collapse.
That does not make such operations ineffective. Delaying a nuclear program can provide valuable time for intelligence collection, diplomatic pressure, and security preparations. But buying time is not the same as permanently eliminating a threat.

The confrontation escalated in June 2025, when Israel launched direct military strikes against Iran’s nuclear infrastructure, followed by American attacks on major facilities.
According to the International Atomic Energy Agency (IAEA), the above-ground section of the Natanz Pilot Fuel Enrichment Plant was destroyed, and electrical supply systems suffered severe damage. Subsequent assessments also identified indications of damage to underground enrichment halls.

These were significant military and intelligence achievements, made possible by detailed knowledge of sensitive infrastructure, technological analysis, and operational planning.
Yet a nuclear program extends far beyond the facilities that house it. It encompasses nuclear material, scientific expertise, skilled personnel, manufacturing capacity, supply networks, and political decisions. Damage to one component, however substantial, does not automatically establish the condition of the entire system.

Before the June 2025 strikes, the IAEA estimated that Iran possessed approximately 440.9 kilograms of uranium enriched to up to 60 percent purity , a level requiring substantially less additional enrichment work to reach the approximately 90 percent commonly associated with weapons-grade uranium.
Possessing such material, however, is not the same as possessing an operational nuclear weapon. Weaponization requires additional technical steps, and enrichment capability alone does not establish a political decision to build a bomb.

These distinctions are essential to an accurate assessment of the threat.

Following the strikes, the IAEA’s ability to maintain effective oversight was severely disrupted. Throughout 2026, restrictions on inspections left the agency unable to independently verify the status and location of all remaining nuclear material.

IAEA Director General Rafael Grossi indicated that a substantial portion of Iran’s uranium enriched to up to 60 percent might be located in a tunnel complex at Isfahan, with additional material potentially remaining at Natanz.

As of October 2026, there was no publicly verified evidence that Iran had resumed uranium enrichment. Yet the absence of confirmed activity does not establish what happened to its remaining stockpile or whether enrichment could be restarted.

This exposes a central paradox: Military action can severely degrade a nuclear program while simultaneously making independent verification of what remains more difficult.

The paradox does not negate the value of military force. It demonstrates why assessing its consequences requires more than measuring physical destruction.

If surviving material cannot be accounted for, remaining equipment cannot be inspected, and reconstruction cannot be independently monitored, an intelligence and diplomatic challenge persists long after the attack.

Under these circumstances, intelligence collection becomes even more important. Satellite imagery can identify construction and equipment movements. Signals intelligence may reveal unusual communications. Human sources can provide insight into decisions and activities concealed from technological surveillance.

But no single source can guarantee a complete picture. Reliable assessments require corroboration, independent analysis, and a clear distinction between confirmed evidence and informed judgment.

An equally important distinction concerns what is known publicly. The IAEA’s inability to verify specific information does not mean Israeli or American intelligence agencies lack classified assessments of the same issues. Without access to that intelligence, outsiders cannot reliably determine what those agencies know.

International verification and national intelligence nevertheless serve different purposes.
Intelligence can expose concealed activities and inform security decisions. Independent inspections provide a basis for monitoring compliance with international commitments. Both are essential to evaluating the long-term consequences of the strikes.

This uncertainty also carries political consequences. Governments considering future agreements, restrictions, or military measures must judge not only the damage already inflicted but the capabilities that may remain. Underestimating those capabilities can be dangerous. So can treating every unresolved question as proof of an imminent threat.

The central responsibility of intelligence is therefore not to eliminate uncertainty, which is rarely possible, but to ensure that decision-makers understand its limits.

This challenge recalls Cassandra, the figure from Greek mythology who could foresee disaster but could not persuade others to believe her warnings. The tension between recognizing danger, assessing its credibility, and acting on incomplete information also lies behind my espionage novel, Cassandra’s Shadow, inspired by the covert struggles of the Middle East.

Unlike Cassandra, intelligence agencies cannot predict the future with certainty. Their responsibility is to examine evidence critically, challenge assumptions, and provide the most reliable assessment possible , including a clear explanation of what remains unknown.

The strikes against Natanz demonstrated that Israel and the United States can inflict substantial damage on critical elements of Iran’s nuclear infrastructure. That achievement should not be understated.

But a lasting strategic outcome depends on more than the targets destroyed. It depends on which capabilities Iran has lost, how long their restoration might take, and whether effective intelligence and verification can establish what remains.

The damage at Natanz is visible. Its full strategic consequences are not yet independently verifiable.

In confronting a nuclear threat, success is measured not only by the ability to destroy a target, but by the ability to establish what remains afterward , and turn military achievement into lasting strategic advantage.