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Iran Conflict 2026
29MAY

US hits Natanz again; no radiation leak

3 min read
08:47UTC

The US hit Iran's main enrichment facility for the second time in this war. The IAEA says 440 kg of near-weapons-grade uranium — enough for roughly ten bombs — remains where it was.

ConflictDeveloping
Key takeaway

Second Natanz strike leaves 440 kg of weapons-grade uranium untouched and unaccounted for.

The US struck Natanz for the second time since the war began on 28 February. Iran confirmed the hit. The IAEA reported no radiation leak 1. The IDF denied involvement — making this a unilateral American operation, not an Israeli strike.

The return to Natanz contradicts two competing narratives. Netanyahu claimed on 18 March that "Iran no longer has the capacity to enrich uranium" . If that were true, there would be no reason to hit the facility again. IAEA Director General Rafael Grossi stated days earlier that "most probably, at the end of this, the material will still be there and the enrichment capacities will be there" . The second strike suggests Washington's own intelligence aligns with Grossi, not with Netanyahu.

Iran holds approximately 440 kg of uranium enriched to 60% — enough, if further enriched to weapons-grade, for roughly ten nuclear devices. Airstrikes can destroy centrifuge cascades. They cannot destroy enriched uranium without causing the radiological contamination both sides claim to want to avoid. The IAEA confirmed no abnormal radiation from Friday's strike, which means the bombs hit hardware, not stockpiles. The core proliferation risk is intact.

Iran's enrichment geography compounds the problem. The IAEA disclosed a previously unknown underground facility at IsfahanIran's fourth known enrichment site — where inspectors have been denied access. Natanz itself has both surface buildings and deeply buried halls; Iran moved critical centrifuge operations underground after the Stuxnet cyberattack destroyed approximately 1,000 centrifuges in 2010. Fordow, another enrichment site, sits under a mountain near Qom. The pattern from two decades of constraint efforts — Stuxnet, the 2021 Mossad sabotage of Natanz, the JCPOA's negotiated limits — is that damage to enrichment hardware is temporary. Iran has rebuilt after every disruption. The 440 kg stockpile, accumulated since Iran began enriching to 60% in April 2021, is the one thing airstrikes cannot safely reach.

Deep Analysis

In plain English

Natanz is where Iran spins uranium into increasingly concentrated form using centrifuges. The US has now struck it twice. But the enriched uranium already produced and stored elsewhere cannot be destroyed from the air. Think of it as bombing a factory: you can wreck the production line, but you cannot destroy the finished goods already in the warehouse. Iran has enough material for roughly ten nuclear weapons if it chose to enrich further — and that stockpile is sitting somewhere the bombs are not falling. The strikes are disrupting future production, not the existing inventory.

Deep Analysis
Synthesis

The persistence of the 440 kg stockpile despite two Natanz strikes exposes a structural gap between the stated objective — preventing Iranian nuclear capability — and the available military instrument. Conventional strikes can degrade production capacity but cannot eliminate accumulated fissile material. This gap will define post-war non-proliferation negotiations more than any battlefield outcome, as the material itself becomes the central unresolved variable in any settlement.

Root Causes

Iran's nuclear programme was structurally redesigned after 2003 to be strike-resistant: dispersed across sites, hardened against conventional munitions, and functionally redundant. The Fordow enrichment facility is bored into a mountain and cannot be penetrated by conventional bombs. Conventional airstrikes against enrichment infrastructure were always a partial instrument against this architecture — a limitation Western planners knew before the first strike.

Escalation

The IDF's explicit denial of Natanz involvement signals deliberate US-Israel compartmentalisation of nuclear targeting decisions. This division could create strategic incoherence: Israel may independently strike targets the US has reserved as negotiating leverage for a diplomatic track. The divergence increases operational unpredictability and reduces the coherence of any coercive signalling Iran receives.

What could happen next?
  • Risk

    Iran's intact 440 kg HEU stockpile becomes the central unresolved obstacle to any post-conflict non-proliferation settlement.

    Medium term · Assessed
  • Precedent

    US unilateral nuclear targeting without IDF involvement establishes a distinct American escalation lane operating outside the bilateral targeting framework.

    Immediate · Assessed
  • Risk

    Repeated strikes on enrichment infrastructure without securing the existing stockpile may compress Iran's weaponisation timeline by creating strategic urgency in Tehran.

    Short term · Suggested
  • Consequence

    IAEA inspection access is effectively suspended during active hostilities, creating a verification black hole that will complicate post-war fissile material accounting.

    Short term · Assessed
First Reported In

Update #44 · Trump: 48 hours to destroy Iran power grid

Times of Israel· 22 Mar 2026
Read original
Causes and effects
This Event
US hits Natanz again; no radiation leak
The second strike on Natanz exposes the gap between political claims that Iran's enrichment is destroyed and the IAEA's assessment that the material and capacity will survive. Airstrikes can damage centrifuges but cannot safely destroy 440 kg of 60%-enriched uranium — the actual proliferation risk.
Different Perspectives
Qatar
Qatar
Qatar holds approximately $12 billion in frozen Iranian assets that Tehran named as the precondition for any Hormuz reopening sequence; with Oman sidelined and no agreed HEU custodian, the asset-routing architecture that any deal requires has no operational channel and no neutral financial intermediary to run it through.
Hengaw and Iranian civilian population
Hengaw and Iranian civilian population
Iranians face an internet capped at 40 per cent by hardware their president cannot dismantle, field killings that leave no court record, and judicial executions running in parallel; Hengaw, based in Norway, is the primary remaining monitor of a repression system the IRGC is deliberately moving beyond auditable records. The real toll is higher than any single monitor's count.
China
China
China supplied deep-packet-inspection hardware that caps Iran's internet at 40 per cent and enables an instant on-demand blackout, and was barred by Trump as a potential HEU custodian on 27 May. Beijing gains from Iran's continued non-alignment with the West while the DPI sale extends Chinese surveillance-technology exports as a geopolitical instrument.
Pakistan
Pakistan
Foreign Minister Ishaq Dar met Rubio in Washington on 29 May, formally inheriting the role of sole active mediator after Oman's forced withdrawal. Pakistan lacks Oman's banking infrastructure for frozen-asset routing and carries its own regional stakes, making it a less structurally neutral broker for the Qatar-held $12 billion sequencing.
Kuwait
Kuwait
Kuwait invoked Article 51 of the UN Charter after absorbing an Iranian ballistic-missile strike on Ali Al Salem Air Base on 28 May, becoming the first Gulf state to make a formal individual self-defence claim in the war. The invocation creates a legal record enabling a future bilateral defence-pact activation without yet triggering it.
Oman
Oman
Oman denied any Hormuz toll plan within hours of Bessent's 28 May threat, absorbing a sanctions warning from the country it has brokered for since 1981. The rapid capitulation preserved the channel formally, but Tehran now knows Washington will threaten its own mediator, which changes Muscat's calculus on how far it can lean into any joint-management architecture.