Download and Print as PDF

Israeli forces struck Iranian nuclear sites at Natanz, Isfahan and Fordow on June 13 aiming to obliterate Iran’s enrichment centrifuges and its stockpile of highly enriched uranium (HEU). According to the International Atomic Energy Agency (IAEA), Iran had enriched its uranium to 60 percent purity, well above the 20 percent threshold needed for some nuclear weapons. Had it been allowed to proceed, it was only a matter of time before Iran would have attained 90 percent pure weapons-grade uranium.

However, possessing weapons-grade uranium does not necessarily mean that Iran is making a bomb. Iran has insisted that its nuclear program remains peaceful and the IAEA has found no evidence of Iran embarking on a formal nuclear weapons program. At the same time, Iran had breached its safeguards compliance by enriching uranium above the 20 percent threshold level and failed to convince the IAEA of the purpose of its HEU stockpile. It is true Iran operates a civilian nuclear power plant (NPP) at Bushehr, with fuel supplied from Russia. Even if Iran wished to be self-sufficient for fuel production, the reactors at the Bushehr NPP would only accept 3 to 5 percent of enriched uranium.

Latent capability in enrichment

The root cause for the conflict can be attributed to Iran’s latent capability to produce HEU. In 2015, Iran signed the Joint Comprehensive Plan of Action (JCPOA) with the P5+1 countries (China, France, Russia, the United Kingdom, the United States and Germany). The JCPOA agreement, which had a 15-year timeframe, would grant the IAEA access to undeclared nuclear sites and place a cap on Iran’s enrichment activities until 2030. The landmark deal was meant to stall but not completely halt Iran’s enrichment capabilities. In return, sanctions on Iran would be lifted in the hope that Iran would ultimately give up its enrichment activities.

However, the United States walked out of the deal in 2018, which led to Iran not honoring its commitments to the JCPOA. The deal was kept intact with the remaining signatories, while at the same time opening the door for nuclear diplomacy to take place between Iran and the U.S. Iran kept up the pressure by accelerating its effort to enrich uranium further, hoping for a stronger bargaining position during negotiations. A series of preliminary negotiations took place in 2025, with some optimism that a deal could be brokered soon.

The conflict between Israel and Iran broke out just before the sixth talk between Iran and the United States was scheduled to take place. Iran blamed the IAEA for inciting the attack. The IAEA had earlier declared that Iran had breached its obligations to the JCPOA as it had consistently failed to provide information on undeclared nuclear materials and activities, thus paving the way for the U.N. Security Council to snap back the sanctions lifted under the JCPOA. In retaliation, Iran threatened to bolster its efforts by building more advanced centrifuges at secure and undisclosed locations to speed up its enrichment activities.

The conflict ended on June 22 when the U.S. Air Force deployed its B-2 bombers and detonated “bunker busters” mainly targeted at the hardened enrichment facilities in Fordow. The United States declared its military operation a success and Israel assessed that Iran’s enrichment capabilities have been scaled back by two years.

Iran remained compliant to the JCPOA until the United States withdrew from the agreement in 2018. If all parties had seen through the entire timeline of the deal, Iran would not have amassed 400 kilograms of HEU of 60 percent purity, as reported by the IAEA, and its enrichment capabilities would have been capped until 2030. It is unknown whether the stockpile of HEU has been completely destroyed, as Iran claimed that it had been moved to a secure location prior to the U.S. strikes. Although key top scientists were killed and some centrifuges destroyed during the brief conflict, the latent expertise of Iran’s enrichment runs deep through its nuclear program and can never be eliminated completely.

More difficult to get Iran to negotiate

Although Iran vows to remain a member of the Non-Proliferation Treaty (NPT), its parliament has decided to stop all cooperation with the IAEA — which is critical because the U.N. watchdog is the only international authority that has the access to verify the status of Iran’s HEU stockpile. Denying the IAEA access to Iran’s ground facilities merely clouds the perception of its HEU stockpile.

The United States could have made the miscalculation that wiping out Iran’s HEU stockpile completely through their military operation will give them leverage at the negotiation table. There is no means of ascertaining the location of the stockpile except via the IAEA. In fact, any future negotiations with Iran will not revolve around its enrichment activities, but rather on Iran’s willingness to grant the IAEA full access to its nuclear facilities for inspection. Under the NPT, every non-nuclear weapons state, including Iran, is obliged to do so already.

Strengthening the NPT

Iran’s decision to remain as a long-standing member of the NPT and keep the cornerstone treaty intact must be commended. Although Iran considered leaving the NPT due to the recent conflict, citing that the NPT does not ensure protection from attacks by nuclear armed states, it should be clear that the NPT does provide negative security assurance in the form of a nuclear weapons-free zone, or NWFZ. (A negative security assurance is when a state with nuclear weapons guarantees it will not use nuclear weapons or make nuclear threats against a non-nuclear weapon state.)

Iran was one of the founding proponents of a Middle East NWFZ, dating back to the 1960s. In keeping with its declaration that its nuclear program is for peaceful purposes, Iran should put its words into action by leading the effort in establishing a NWFZ among Arab countries. Such a zone would not only reinforce the commitment of all parties to neither develop nor possess nuclear weapons, but also enhance peace and security by eliminating the threat of nuclear weapons from the region. A Middle East NWFZ would serve as an important confidence-building mechanism and could eventually encourage all states in the region to sign onto and fully implement the obligations of the NPT.

About the Author

Alvin Chew is a senior fellow at the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University (NTU), Singapore, as well as a member of the Asia-Pacific Leadership Network (APLN).

Disclaimer: The opinions articulated in this work represent the views of the author(s) and do not necessarily reflect the position of the Asia-Pacific Leadership Network or any of its members. The APLN’s website is a source of authoritative research and analysis and serves as a platform for debate and discussion among our senior network members, experts and practitioners, as well as the next generation of policymakers, analysts and advocates. Comments and responses can be emailed to apln@apln.network.

Image: Eight Israeli Air Force F-15I Ra’am strike fighter jets of 69 Squadron “Hammers” at Hatzerim Airbase high above Israel on their way to attack Iran in mid June 2025. Wikimedia Commons.

This article was published in The Korea Times on 13 August 2025. You can find the original article here.