As international efforts continue to address Iran’s nuclear ambitions, one of the world’s most closely watched experts on nuclear proliferation says the country’s program has suffered a major setback but remains unresolved. David Albright, a physicist, former inspector for the International Atomic Energy Agency (IAEA) and founder of the Institute for Science and International Security, argues that military action has delayed Iran’s capabilities but cannot guarantee the end of its nuclear ambitions.
In an interview with EL PAÍS, Albright described the current situation as a critical moment following years of failed negotiations, international inspections and escalating tensions. His assessment is based on decades of experience studying nuclear programs, including his work as an IAEA inspector in Iraq during the 1990s and his extensive research into Iran’s activities.
The discussion comes after Washington and Tehran agreed on a new memorandum of understanding focused on nuclear issues. Albright expressed caution, noting that previous agreements between Iran and the IAEA over the past 15 to 20 years had repeatedly failed because Tehran did not provide sufficient access to facilities and personnel.
He said the new memorandum could potentially address unresolved issues, but emphasized that it does not automatically require Iran to return to full compliance with its obligations under the Nuclear Non-Proliferation Treaty. According to Albright, the United States would need to apply significant pressure to ensure that Iran fulfills those commitments.
When asked whether the agreement could prevent Iran from building a nuclear weapon, Albright said the memorandum alone would not be enough. However, he pointed to the damage caused to Iran’s nuclear infrastructure, arguing that the country’s capabilities have been significantly weakened.
He said Iran currently does not appear to have operational centrifuges capable of producing uranium at the level required for military purposes. In addition, facilities involved in the production of a nuclear weapon have been heavily damaged by bombing. Rebuilding those capabilities, he estimated, would take more than a year.
The question of international inspections remains central to any future agreement. Albright said the return of UN inspectors to the ground would be essential but expressed doubts over whether Iran would accept the level of transparency required.
For inspections to move forward, he said Iran would need to provide a complete declaration of its nuclear activities and allow access to military sites and individuals connected to its weapons program. Without clarity over whether Tehran intends to cooperate, he argued, the effectiveness of any inspection process would remain uncertain.
Before the US and Israeli attacks in June 2025, Albright estimated that Iran was only months away from having enough weapons-grade uranium for a nuclear device, possibly even enough material for several weapons. At that time, he said, the country could have completed the necessary steps within approximately six months.
The damage caused by the war has changed that timeline. Albright now estimates that Iran would need at least a year to complete the process required to build a nuclear weapon. He explained that Tehran would need to reconstruct damaged facilities, overcome technical setbacks and rebuild expertise lost during the conflict.
According to Albright, Iran had previously reached a point where officials were confident their weapon design would work. Following the attacks, that confidence has been reduced. He noted that developing a nuclear weapon would require Iran to establish a small enrichment facility capable of producing uranium enriched to 90%, the level generally associated with nuclear weapons.
The expert also addressed the reasons behind the renewed military confrontation after previous strikes had already damaged Iran’s nuclear infrastructure. He said satellite images following the June 2025 war showed that Iran had been carrying out recovery operations at facilities linked to nuclear weaponization activities.
Albright said Tehran appeared to be attempting to restore elements of its nuclear capability, including work connected to a new site north of Tehran and efforts to clear entrances to tunnels in Isfahan, where much of Iran’s enriched uranium is believed to be stored. He said it remained unclear how advanced or comprehensive those efforts were, but the activity suggested an attempt to rebuild.
For Albright, the central lesson from decades of nuclear history is that military force has limits. He pointed to Iraq in the 1990s, South Africa in the late 1980s, and former Soviet states such as Belarus, Kazakhstan and Ukraine, which gave up nuclear weapons inherited after the Soviet Union’s collapse.
According to him, nuclear programs ultimately end only when governments themselves decide to abandon them. Bombing campaigns can delay progress, but they do not erase scientific knowledge or technical expertise.
“The knowledge cannot be killed,” Albright said, explaining that nuclear expertise exists beyond individual scientists because it is preserved through research, documents and accumulated experience. He described the recent conflict as a significant test of how far military action can push back a nuclear weapons program.
His conclusion was that Iran’s nuclear program has suffered a serious setback but has not been eliminated. The country, he said, could still choose to rebuild its capabilities if its leadership decides to pursue that path.
Albright also rejected comparisons between Iran and South Africa’s decision to abandon its nuclear weapons program. He argued that Iran remains a geopolitical rival of the United States and other countries, and that political conditions are fundamentally different.
Responding to claims by US President Donald Trump that the war had ensured Iran would never obtain a nuclear weapon, Albright said he did not agree. He estimated there remains a 50% possibility that Iran will attempt to restart efforts toward developing nuclear weapons.
However, he added that Tehran may now be more cautious because it cannot be certain it could achieve a nuclear capability quickly enough to avoid detection. The future of Iran’s nuclear program, he said, will depend less on the damage caused by military strikes and more on the decisions made by Iran’s own government.
