Between a fatwa and war: how Iran makes sense of its nuclear capability

Iran has publicly reaffirmed its intent to protect its nuclear stockpile amid the ongoing US-Israel military campaign launched on February 28, 2026, which ki...

What Happened

Iran has publicly reaffirmed its intent to protect its nuclear stockpile amid the ongoing US-Israel military campaign launched on February 28, 2026, which killed the country's supreme leader and targeted military and nuclear infrastructure.
The fatwa issued by the late Supreme Leader Ali Khamenei — declaring the development and use of nuclear weapons forbidden under Islamic law — has come under renewed scrutiny, as in Shia jurisprudence a fatwa is tied to the lifetime of the issuing religious authority and does not automatically bind his successor.
Iran's nuclear decision-making is now viewed by analysts as a purely political and strategic calculation rather than one constrained by religious doctrine, with a senior advisor to Khamenei having stated in 2025 that Iran would have no choice but to pursue nuclear weapons if attacked by the United States or its allies.
The IRGC (Islamic Revolutionary Guard Corps) has framed the nuclear stockpile as a national security asset, while Iran's new leadership navigates between retaining NPT membership and the growing domestic pressure to move toward weaponisation.

Static Topic Bridges

The Nuclear Non-Proliferation Treaty (NPT)

The NPT, opened for signature in 1968 and entering into force in 1970, is the cornerstone of the global nuclear non-proliferation regime. It has three pillars: non-proliferation (non-nuclear states pledge not to acquire weapons), disarmament (nuclear-weapon states pledge to work toward elimination), and the peaceful use of nuclear energy.

Under Article II, non-nuclear-weapon states pledge never to acquire nuclear weapons.
Under Article III, non-nuclear-weapon states must conclude Comprehensive Safeguards Agreements (CSAs) with the IAEA to verify compliance.
Under Article VI, nuclear-weapon states are obligated to pursue disarmament negotiations in good faith.
Iran signed the NPT in July 1968 and ratified it in February 1970 as a non-nuclear-weapon state.
The IAEA Board found Iran in non-compliance with its safeguards agreement in June 2025.

Connection to this news: Iran's reaffirmation that it will protect its nuclear stockpile raises the question of whether it intends to remain an NPT party in good standing or whether the calculus of war will push it toward withdrawal under Article X, which allows a state to withdraw with 90 days' notice if it determines that extraordinary events have jeopardised its supreme interests.

Iran's Nuclear Fatwa: Religious Ruling vs. Strategic Doctrine

Supreme Leader Khamenei issued an oral fatwa in October 2003 prohibiting the production, stockpiling, and use of nuclear weapons, describing them as forbidden (haram) under Islamic law on the grounds that they cause indiscriminate civilian casualties — a prohibition rooted in classical Islamic jurisprudence regarding weapons that harm non-combatants. The fatwa was formally articulated at an IAEA meeting in Vienna in August 2005.

In Shia jurisprudence, a fatwa is issued by a living marja (grand religious authority) and is binding on his followers during his lifetime; it does not automatically transfer to a successor.
Khamenei was killed in the US-Israeli strikes on February 28, 2026, rendering his fatwa legally extinct under Shia doctrine.
A former Iranian diplomat has noted that fatwas in Jaafari Shia jurisprudence are "issued in accordance with developing circumstances" and are not permanent.
Iran's decisionmaking has historically been guided by the principle of "regime expediency" (maslahat), which can override strict religious rulings when the survival of the state is at stake.
In early 2025, IRGC commanders pressured Khamenei to rescind the ban, and a senior Khamenei advisor publicly stated Iran would pursue nuclear weapons if existentially threatened.

Connection to this news: The death of the fatwa's issuer alongside the existential military pressure of an ongoing war effectively removes the religious-legal constraint on Iran's nuclear decision-making, making the outcome now entirely a function of strategic and political calculus.

IAEA Safeguards and Non-Compliance

IAEA safeguards are technical verification measures applied under safeguards agreements concluded between the IAEA and individual states. For NPT non-nuclear-weapon states, the standard is a Comprehensive Safeguards Agreement (CSA), and an Additional Protocol can strengthen inspection rights.

Iran's CSA with the IAEA was concluded in 1974.
Iran signed but never fully implemented the Additional Protocol, limiting inspectors' access.
The IAEA Board found Iran in non-compliance with its safeguards obligations in 2005 and again in June 2025, triggering mandatory referral to the UN Security Council.
Iran has accumulated uranium enriched to 60% purity — far above the 3–5% level needed for civilian power generation but below the 90%+ weapons-grade threshold.

Connection to this news: The military context of the 2026 conflict and the lapse of the fatwa compound existing IAEA non-compliance concerns, raising the risk of Iran either attempting a covert "breakout" to weapons-grade material or formally withdrawing from the NPT.

Key Facts & Data

The NPT was opened for signature in 1968; Iran ratified it in February 1970.
Khamenei's fatwa against nuclear weapons was first issued orally in October 2003 and formally restated at the IAEA in August 2005.
Khamenei was killed on February 28, 2026, in a joint US-Israeli strike during Operation Epic Fury.
Iran has enriched uranium to 60% purity — significantly above civilian reactor grade (3–5%) but below weapons grade (90%+).
In Shia jurisprudence, a fatwa dies with the issuing marja, making Khamenei's prohibition legally non-binding on his successor.
The IAEA Board found Iran in non-compliance with its safeguards agreement in June 2025.
Iran's Assembly of Experts appointed Mojtaba Khamenei, son of the late supreme leader, as successor.
The 2026 war began February 28 when the US and Israel launched nearly 900 strikes in 12 hours targeting Iranian military infrastructure and leadership.