Seven decades of enrichment and pressure: How Tehran shaped the nuclear equation

 

For seven decades, “Iran’s nuclear” has not been a purely technical file, but an arena of conflict: the will of a state that seeks to establish a “sovereign right” and build a deterrence/bargaining capacity, the will of the non-proliferation regime led by the International Atomic Energy Agency and with it the Security Council, and the will of a territory that sees any progress in enrichment a transformation that redraws the balance of power and the lines of war and peace in the Middle East.

 

Below is a historical account of the most prominent turns, highlighting the roles of the Atomic Energy Organization of Iran (AEOI) from the beginnings to the latest developments:

 

1) Beginnings: “The Atom for Peace” before it became a power policy (1956–1979)

 

In 1956, the Atomic Energy Organization of Iran (AEOI) was officially established, after its activities were limited in a research center at the University of Tehran. This came as part of a broad American program entitled “Atom for Peace”, and Washington provided Tehran with a research reactor in the context of the strategic partnership between the Pahlavi government and the United States.

 

In 1958, Iran joined the International Atomic Energy Agency, and in 1968 signed the Treaty on the Non-Proliferation of Nuclear Weapons, and the Iranian parliament ratified it in 1970. Officially, these steps were to ensure peaceful use, but they did not dispel undeclared ambitions.

 

In February 1974, after India tested its nuclear bomb, an interview with Pahlawi quoted the Le Monde newspaper as saying that “Iran will possess a nuclear weapon faster than anyone expects.” The memoirs of Asdallah Alam, the minister of the royal court, also reveal that the Shah seriously considered during the 1970s about owning an atomic bomb.

 

The program then expanded with huge contracts: an agreement with the German company “Kraft and Union” (Siemens branch) to build two 1,200 MW reactors in Bushehr, negotiations with France’s Framatom for two additional reactors, and an injection of $1 billion into the French Eurodiv project to enrich uranium in order to secure fuel. The organization’s budget in 1976 amounted to about $1.3 billion, becoming the largest economic institution in Iran after oil.

 

For two decades, the United States continued to oppose enrichment inside Iran, before the file turned into one of the topics of dispute between the Shah and Washington.

 

2) The return of the “nuclear” as an idea of national security (1981–1989)

 

With the February 1979 revolution, Western companies withdrew and the program stopped, but the outbreak of war with Iraq quickly brought nuclear back to the forefront of security thinking.

 

Akbar Hashemi Rafsanjani, Speaker of the Shura Council during the years of War and Deputy Commander-in-Chief of the Armed Forces, acknowledged in an interview on 2015-10-26 that Iran has sought since the beginning of the war to possess nuclear weapons, adding: “We have sought to have such a possibility for a day when our enemy may want to use nuclear weapons.”

 

In the early 1980s, Iran illegally acquired nuclear technology through the network of the Pakistani scientist Abdulqadeer Khan, who is the father of Pakistan’s nuclear bomb and the most prominent intermediary for the transfer of nuclear technology. This included P-1 centrifuges and technical knowledge related to the enrichment process. In 1983, U.S. intelligence reported that Khan sold knowledge and equipment to Iran, North Korea and Libya, and the IAEA began investigations that ended with Pakistan’s “charge”.

 

During that period, Iran began experiments with 4% enrichment through the redesign of the centrifuge, and in 1985 the device was renamed the P-1 to IR-1. In 1987, Iran also worked to reach the “yellow cake” (uranium oxide) with the help of a Chinese expert, according to the report of the Iran International channel, a stage that laid the technical basis for the sut.

 

In July 1988, in the last year of the war, Mohsen Rezaei, then commander-in-chief of the Revolutionary Guards, sent a letter to Khomeini reviewing the requirements for achieving “military victory” over Iraq, the first of which was “nuclear weapons”.

 

3) Post-Cold War: The Collapse of the Soviet Union and the Siege of Iraq (1990–2001)

 

United Nations Resolution 661 was issued on August 6, 1990 to impose an international blockade on Iraq, and provided for “suffocating economic sanctions”. The consequences of the blockade have prompted many experts to leave Iraq. There was unofficial news about Iran contracting Iraqi nuclear experts to work on its nuclear project.

 

In the same period after the collapse of the Soviet Union in 1991, Russia formed a joint research organization with Iran under the name of “Persepolis”, which provided Iran with Russian nuclear energy experts and technical information. Five Russian institutions, including Russia’s Federal Space Agency, have helped Tehran improve its rockets.

 

4) Big Revelation: Natanz and the Beginning of the International Crisis (2002–2003)

 

In August 2002, the MEK revealed that Tehran was building an industrial-scale enrichment facility in Natanz, and that it conducted secret enrichment operations without informing the International Atomic Energy Agency.

 

In February 2003, the director of the agency, Muhammad ElBaradei, visited Tehran and inspected Natanez. In the summer of 2003, IAEA inspectors conducted environmental sampling that revealed the effects of high-enrichment in some places of 79%, exceeding Iranian claims of peaceful use.

 

Europe responded with unprecedented diplomatic move: In October 2003, the foreign ministers of Britain, France and Germany (Jacques Straux, Dominique de Villepin, Joscha Fischer) visited Tehran in a rare joint visit, and snewed Iran’s approval to suspend enrichment to avoid referring to the Security Council. The leadership of the file was assigned to Hassan Rouhani, then Secretary of the Supreme National Security Council, by order of Khamenei.

 

5) “Amad”: The parallel military project (2003–2004)

 

The Iran International report indicates that the announcement of the suspension of “Amad” in 2004 did not mean the end of the military process, as the work continued under the name of “sub-project 110” related to neutron activities and lightners used in a nuclear warhead.

 

The point remains the focus of conflict between the official Iranian narrative denying the search for weapons, Western intelligence accounts accused, and agency reports demanding explanations about “uranium effects” and “undeclared sites” at different periods.

 

6) Paris Agreement and Collapse: Rouhani and Larijani Chapter (2004–2006)

 

In November 2004, Iran and the three European countries reached the “Paris Agreement” that extended the suspension to include the manufacture of centrifuge parts, but the negotiation of “substantive guarantees” preventing the program from directing for military purposes quickly stalled.

 

In early 2005, Hassan Rouhani announced that the leader wanted to break the enrichment suspension before the end of President Mohamed Khatami’s term, and the slogan is dedicated: “Nuclear energy is our legitimate right.” In August 2005, Ali succeeded Larijani Rouhani in command of the file. In January 2006, Iran restarted its facilities, and the IAEA Board of Governors decided in February 2006 to refer the file to the UN Security Council.

 

7) Sanctions and Fertilization 20%: Ahmadinejad era (2006–2013)

 

The Security Council issued a series of resolutions under Chapter VII, most notably the June 2010 resolution, which imposed wide sanctions and recommended the inspection of aircraft and ships associated with Iran. This came after Iran announced 20% uranium enrichment under the pretext of securing the fuel of the Tehran research reactor, after Argentina was supplying it with fuel before the deal was stopped.

 

In December 2010, the United States, Britain and the European Union imposed sanctions on the Central Bank of Iran, starting a phase of “crippling sanctions” that targeted oil, banks and shipping.

 

Security, a number of Iranian nuclear scientists were assassinated between 2010 and 2012 in incidents largely attributed to Western and Israeli intelligence services without official responsibility.

 

8) Khamenei’s fatwa: a diplomatic tool or a religious doctrine?

 

On April 4, 2010, he submitted a written text from the Iranian leader to the “First International Conference on Nuclear Disarmament and Non-Proliferation” in which he said: “We consider the use of these weapons forbidden, and we believe that it is the duty of everyone to seek to preserve humanity from this great disaster.”

 

Western forums received this speech as a prohibition of the manufacture of nuclear weapons, while the text speaks of the sanctity of “use” and not “industry” or “retention”. Some interpreters go on to say that the manufacture of nuclear weapons or possessing the ability to manufacture it may be considered a legitimate duty based on the words of the Almighty: “And prepare for them what you can of strength” (Al-Anfal: 60).

 

Even if it is considered forbidden, the idea of the absolute powers of the “guardian of the jurist” to change the provisions if he sees the interest of the Islamic State. Also, the complex for the diagnosis of the interest of the regime is the foundations of legislation for what it deems as the interest of the regime, even if it violates the constitution or the principles of religion.

 

For this reason, statements followed in the stage of stalling negotiations (2021-2022) hinting at the possibility of the fatwa: Former Intelligence Minister Mahmoud Alawi linked the sanctity of ownership to “Iran’s failure to be under severe pressure”, and Ahmed Bakhshaish, a Jordanian, described nuclear possession as “the only solution,” stressing that the fatwas “change with the change of time and place.” Many similar statements.

 

9) Bargam: Historical Agreement and Then Breaking It (2013–2018)

 

Hassan Rouhani’s presidency in 2013 opened the door to direct negotiations between Tehran and Washington. Sultan Qaboos has played the role of mediator since 2011 and conveyed to Tehran a letter from Barack Obama containing an initial acceptance of enrichment within Iran.

 

The United States wanted an agreement that included nuclear and missile, Iran’s regional interventions and human rights, while Iran insisted on dealing with the files successively and linked any subsequent negotiation to the completion of the nuclear agreement first. Obama was determined to reach an agreement before the presidential election, so 22-month negotiations described as the July 2015 Comprehensive Plan of Action ended, and the Security Council passed Resolution 2231 to lift sanctions on a schedule. After that, Iran refused to return to negotiating the other files.

 

However, Khamenei described the agreement in his August 2015 speech as an American attempt to penetrate Iran, and stressed Tehran’s adherence to the support of the proxy militias. In October 2015, weeks after the signing, the Revolutionary Guards conducted a test of a ballistic missile on its side with slogans against Israel in Hebrew, which caused tension in the Security Council. In January 2016, he announced the implementation of the agreement and the lifting of UN, European and American sanctions related to the nuclear file.

 

With Donald Trump coming to power in early 2017, pressure mounted to introduce additional files into the negotiation, and with Iran’s refusal, Trump described the deal as “bad.”

 

Behind the diplomatic curtain, Iran, according to Western and Israeli intelligence narratives, was proceeding with a parallel military program. An Israeli intelligence operation, which included the seizure of a documentary archive from the Shurabad area of Tehran on the night of January 31, 2018, revealed what was known as the “Amad Project” under the supervision of Mohsen Fakhrizadeh, and spoke of an explosive lightning test at the Mariwan site near the city of Abada.

 

In May 2018, Washington withdrew from Barjam and reimposed sanctions. Iran announced the continuation of the commitment in principle, but in January 2020, following the assassination of Qassem Soleimani, it announced the abandonment of the last practical border imposed by the enrichment agreement.

 

10) Post-Berjam escalation: about 60% and above (2020–2025)

 

In December 2020, after Joe Biden’s victory, the Iranian parliament, at the behest of Khamenei, passed the “Strategic Procedure Law” that obliged the government to suspend the Additional Agreement Protocol and end the surprise inspection of the agency’s inspectors, and begin to enrich 20% and increase inventory, which practically means blowing up the inspection framework of Berjam.

 

Also in December 2020, Mohsen Fakhrizadeh was assassinated in the suburb of Damamond in a process attributed to Israel. In April 2021, Iran announced the start of enriching 60% under the pretext of “securing fuel for nuclear submarines”.

 

According to what Iran International sources call the “Khan road map”, Iran is no longer separated from the bomb except by the jump from 60% to 90%, which is the leap that was historically the technical “bottle neck”, but according to the same sources, its obstacles have decreased after the cancellation of the terms of the technology.

 

In May 2025, a comprehensive report by the International Atomic Energy Agency revealed that Iran continues to refuse to cooperate effectively with inspectors. In the first quarter of 2025, negotiations with the Trump administration resumed…