Israel and the United States prioritized degrading Iran's nuclear weaponization abilities during Operation Roaring Lion and Operation Epic Fury over targeting nuclear enrichment sites, according to an Institute for Science and International Security analysis of satellite imagery. The strategic focus on weapons development rather than enrichment infrastructure represents a deliberate choice in military planning with significant implications for Iran's timeline to nuclear capability.
The analysis found that little new damage was done to Iranian nuclear enrichment facilities already destroyed in strikes during the 12-day war one year ago. Instead, facilities and infrastructure related to the weaponization of enriched uranium, including development sites, were targeted. This distinction matters substantially: enrichment can theoretically be resumed, but weaponization requires specialized expertise, facilities, and testing infrastructure that cannot be quickly rebuilt.
Targeting Weaponization Infrastructure
One key target analyzed by the institute was the Min Zadai site, which it said is suspected to have played a key role in Iran's attempts to recover nuclear weapons capabilities after the June 2025 strikes. On March 3, the IDF announced strikes on the complex, describing it as a partially underground "nuclear headquarters" where nuclear scientists were developing key components for nuclear weapons systems. Reporting by the French newspaper Le Monde suggested the Min Zadai complex was involved in the metallurgy of nuclear weapons cores—the most technically demanding aspect of weapons development.
Another site was Taleghan 2, a highly fortified facility within Iran's Parchin military complex that has been used in Iran's nuclear weapons testing and development of advanced explosives. The fortification level of this facility underscores its importance to Iran's weapons program and the difficulty of targeting it.
Universities with connections to Iran's development of nuclear weapons were also targeted. Tehran's Malek Ashtar University, which the IDF directly tied to nuclear weaponization, and an adjacent laboratory-type building connected to the university by a footbridge were heavily damaged in strikes. The university-adjacent laboratory was built right next to the Mojdeh site, a nuclear site destroyed by Israeli strikes one year ago, suggesting a deliberate pattern of reconstructing capabilities in proximity to previously targeted locations.
Military Research Complexes Under Attack
Imam Hussein University, a key Islamic Revolutionary Guard Corps university, was struck on March 10 for hosting an underground weapons research and development complex used by the IRGC for experimentation and testing related to ballistic missiles. The targeting of university-based research facilities highlights the dual-use nature of Iran's nuclear program, with academic institutions serving as covers for military weapons development.
In addition to at least four sites specifically tied to nuclear weaponization by the IDF, the Institute for Science and International Security analysis identified three other targeted sites likely to have also been used in the development of nuclear weapons. The institute said the destruction of key weaponization sites likely significantly increased the time it would take for Iran to complete the production of nuclear weapons.
The campaign reflects a strategic assessment that degrading weapons development capabilities provides more durable security benefits than targeting enrichment facilities, which can be rebuilt or relocated. By focusing on the most technically demanding and time-intensive aspects of weapons development—the metallurgy, testing, and engineering of nuclear cores—the strikes impose substantial delays on Iran's ability to weaponize its enriched uranium stockpile.
Why This Matters:
The targeting strategy reveals a sophisticated understanding of nuclear weapons development timelines and bottlenecks. While enrichment can theoretically resume if sanctions are lifted or agreements collapse, weaponization requires sustained institutional knowledge, specialized testing facilities, and years of experimentation. By destroying these facilities and dispersing the scientific cadre, the strikes have imposed what analysts describe as a significant timeline extension on Iran's nuclear weapons capability. This has direct relevance to ongoing negotiations: it increases the window for diplomatic solutions and raises the cost to Iran of pursuing weapons development. The focus on military research universities also demonstrates how dual-use academic institutions can serve as proliferation vectors, a concern relevant to broader nonproliferation policy. The destruction of multiple sites suggests a coordinated campaign designed to degrade Iran's entire weapons development ecosystem rather than a single strike on a single facility, making reconstitution more difficult and time-consuming.