Over more than sixty years, Iran’s nuclear program has gone through monarchies, revolutions, wars, sanctions, and international negotiations. It survived the fall of the Shah, the eight-year war with Iraq, Western pressures, targeted assassinations of scientists, and more recently, the Israeli and US bombings of 2026 which – according to Trump – “completely and totally obliterated” Tehran’s nuclear program.
Born as a civilian energy project, it progressively transformed into one of the most delicate geopolitical dossiers on the planet. And even today, the question dividing diplomats, military, and intelligence services remains the same: no one anymore wonders if Iran really wants to build atomic warheads and mount them on medium-range missiles. Rather, the question is: once nuclear weapons are ready, will the Ayatollahs immediately launch them at Israel, erasing forever the only democracy in the Middle East and triggering a global catastrophe, or is their goal to achieve nuclear deterrence capability without crossing the point of no return?
Probably, even in the deep Iranian bunkers, military and civilian leaders are asking themselves the same question, likely fighting among themselves. The absence of a real usable leader (the theoretical new supreme leader Mojtaba Khamenei has never made an appearance, neither in person, nor in video, nor even with an audio message or a handwritten manuscript signed by him) makes the situation even more dangerously fluid since it is unknown whether there is a true – albeit hidden – authority recognized by the leadership, or if each one is proceeding on their own carrying forward their personal agenda.
From the Shah’s “Atoms for Peace” to the Islamic Revolution
The origins of the Iranian nuclear program date back to the 1950s. In 1957 Tehran joined the US “Atoms for Peace” program, promoted by the Eisenhower administration. At the time, Iran was a close ally of the United States and no one imagined that, a few decades later, it would become one of their main adversaries.
In 1967 Washington provided Tehran with a small 5 MW research reactor, installed at the Tehran Nuclear Center and fueled with highly enriched uranium.
In the 1970s, Shah Mohammad Reza Pahlavi developed an extremely ambitious program. Strong from enormous oil revenues, it envisaged the construction of 23 nuclear reactors for a total capacity exceeding 20 GW. The goal was to free oil and gas from domestic use and dedicate them exclusively to export, while domestic energy needs would be met solely by peaceful nuclear fission.
In 1974, the Atomic Energy Organization of Iran (AEOI) was established. The German Siemens-KWU began construction of two reactors of about 1,300 MW in Bushehr, and France guaranteed Tehran a 10% stake in the Eurodif consortium, intended for uranium enrichment.
Then came the 1979 Islamic Revolution and the hostage crisis at the American embassy. Most Western technicians, engineers, and scientists left the country; a minority who sensed an opportunity to enrich themselves switched allegiance to be courted by the new regime; international contracts were canceled and the nuclear program seemed destined – at least apparently – to disappear.
The war with Iraq and the program’s rebirth
The war against Saddam Hussein changed everything. Between 1980 and 1988, the Bushehr facilities were repeatedly bombed by Iraqi air attacks and guided missiles, and Tehran developed the conviction that regime survival required greater technological self-sufficiency. Declared peaceful but – increasingly explicitly – also military.
In the 1990s, after the collapse of the Soviet Union, Russia became Iran’s main nuclear partner. In 1995 Moscow signed an agreement to complete the first Bushehr reactor, which would only become operational in 2011.
Meanwhile, Iran progressively developed the entire nuclear fuel cycle. The Saghand pitchblende mines were established to extract uranium, the Ardanak processing and Isfahan conversion plants to obtain and process uranium yellowcake, the Arak heavy water production center, and above all, the gigantic enrichment complex at Natanz.
In 2002, the Iranian opposition in exile made public the existence of Natanz and Arak. It was the beginning of a long crisis with the International Atomic Energy Agency and Western powers.
The IAEA found that for nearly twenty years Tehran had conducted clandestine nuclear activities, fooling inspectors who were completely unaware of entire facilities’ very existence. Thus began a long period of inspections, UN resolutions, and economic sanctions.
Centrifuges, enriched uranium, and the 2015 compromise
The heart of the Iranian program has always been uranium enrichment.
Natural uranium contains just 0.7% U-235. To fuel a nuclear power plant, concentrations between 3 and 5% are required; to build an atomic bomb, 90% is needed.
Isotopic separation occurs through long chains of ultracentrifuges rotating at speeds close to 70,000 revolutions per minute. The process is lengthy and consumes an enormous amount of energy. For this reason, the existence of large thermoelectric plants in areas that do not justify large civilian consumption is often the first sign that, somewhere underground, long chains of centrifuges are in full operation.
Iran started with the IR-1 centrifuges, derived from the Pakistani P-1 project, then developed more sophisticated models like IR-2m, IR-4, IR-6, and IR-8. Between 2006 and 2013, the number of installed centrifuges exceeded 19,000 units.
International sanctions hit the Iranian economy hard, contributing to the election of President Hassan Rouhani and the opening of negotiations with the United States, Russia, China, France, the United Kingdom, and Germany.
On July 14, 2015, the Joint Comprehensive Plan of Action (JCPOA) was born.
The agreement limited enrichment to 3.67% (the minimum necessary for exclusively civilian uses), reduced operational centrifuges from about 19,000 to just over 5,000, imposed the conversion of the underground Fordow facility into a research center, and redesigned the Arak heavy water reactor to prevent military use.
In exchange, many international sanctions were lifted.
And for several years the system worked.
The return of Trump and the progressive collapse of the JCPOA
In May 2018, Donald Trump unilaterally decided to withdraw the United States from the agreement, judging it too favorable to Tehran. Sanctions were reintroduced and the Iranian economy once again faced difficulties.
Iran gradually responded by abandoning the limits set by the JCPOA.
In 2021, it began enriching uranium to 20%.
Subsequently, it reached 60%, a level that technically already represents about nine-tenths of the work needed to reach weapons-grade uranium.
Meanwhile, the IAEA reported increasing difficulties in monitoring activities and verified the undeniable – though unjustifiable – presence of enriched uranium particles at undeclared sites.
According to the World Nuclear Association, before the 2026 war, Iranian stocks included 2,391 kilograms of uranium enriched to 2%, 6,024 kilograms at 5%, 184 kilograms at 20%, and about 441 kilograms enriched to 60%.
These last quantities represent the main concern of Western analysts: raising material already enriched to 60% up to 90% requires relatively short times. In theory, that amount would be sufficient to obtain fissile material for about eleven nuclear devices, to be launched with ballistic missiles Tehran already possesses. Among these, the Shahab-3 and Khorramshahr can hit targets up to 2,000 km away.
But even the lower enrichment fractions cause strong concern precisely because, despite the still low enrichment, they are far along the path leading to weapons-grade uranium.
The 2026 war and the new agreement
The latest war between Israel, the United States, and Iran severely hit the nuclear program.
The Isfahan facilities suffered significant damage: chemical laboratories, uranium conversion structures, and sites dedicated to advanced centrifuge production were attacked. Other nuclear infrastructures were also targeted by Israeli and American operations. Trump repeatedly claimed that the Iranian nuclear program had been definitively wiped out by targeted bombings, assuring that Tehran would never be able to rebuild it. But the objective reality seems, once again, very different from the outbursts on social media of the most powerful man on Earth.
Meanwhile, the only certainty is that Bushehr, the only operational nuclear power plant, remained untouched by attacks: satellite analyses show unequivocal images and thermal footprints proving its full activity even during wartime.
But the biggest problem is another.
No one knows precisely where the enriched uranium stocks ended up and in what condition the thousands of centrifuges necessary to continue the program are. Destroyed? Irretrievably buried under tens of meters of rock? Easily excavatable or not? Intact and hidden elsewhere? The IAEA has been unable for months to provide a complete analysis of the situation.
In recent hours Washington and Tehran have signed a preliminary fourteen-point memorandum, which froze hostilities and opened a sixty-day negotiation window. The agreement provides for Iran’s reaffirmation of its commitment not to develop nuclear weapons – at least for the first 60 days – and cooperation with the IAEA in managing the accumulated enriched uranium. Sanctions relief and a gradual reintegration of Iran into international energy markets are also planned.
However, the central issue remains unresolved.
The United States demand verifiable and lasting guarantees. Iran continues instead to consider uranium enrichment “a sovereign and inalienable right” – and here lies the paradox of this entire story.
After sixty years of crises, revolutions, sanctions, and wars, Washington and Tel Aviv have shown they can slow down Iran’s nuclear program, but not eliminate it forever. On the other side, many leaders of the Islamic Republic seem to have reached the opposite conviction: in an increasingly unstable Middle East, the ability to quickly reach the bomb can represent – if not the destruction of the Jewish State, their eternal enemy – at least the best insurance for the survival of the Islamic regime itself.
If so, the war that – perhaps – is now ending would have produced a paradoxical result: not the abandonment of the nuclear option, but its further legitimization in Tehran’s eyes.
And, once again, the fundamental problem remains unchanged: how to prevent Iran from reaching the atomic threshold without convincing it that now is the right time to cross it.
