The United States escalated its involvement in Israel’s conflict with Iran by deploying massive “bunker-buster” bombs on Iran’s Fordo nuclear enrichment plant, a facility embedded deep within a mountain and unscathed by Israel’s week-long offensive. A US official, speaking anonymously before an official briefing, confirmed the use of these bombs in Sunday’s strike.
The US, uniquely equipped to deploy such weapons, had signalled potential action with B-2 stealth bombers moving toward Asia on Saturday. Israeli leaders openly sought President Donald Trump’s support for their campaign against Iran, though they hinted at alternative plans to target Fordo.
The extent of damage to Fordo remains uncertain, with the strike potentially jeopardising hopes for Trump’s proposed nuclear talks with Iran and risking US entanglement in another Middle East conflict.
The “bunker-buster” refers to the GBU-57 A/B Massive Ordnance Penetrator, a 30,000-pound (13,600-kg) precision-guided bomb designed to destroy deeply buried bunkers, capable of penetrating 200 feet (61 metres) underground, according to the US Air Force. Multiple bombs can be dropped sequentially to deepen impact.
Carrying a conventional warhead, the GBU-57 risks releasing nuclear material if used on Fordo, where the International Atomic Energy Agency (IAEA) confirms Iran produces highly enriched uranium. However, IAEA reports indicate Israel’s strikes on Natanz, another Iranian nuclear site, caused contamination confined to the facility.
Fordo, Iran’s secondary enrichment site after Natanz, lies 80 metres (260 feet) beneath rock near Qom, operational since 2009. Protected by Iranian and Russian air defences—likely weakened by Israel’s campaign—it faces scrutiny as Israeli Prime Minister Benjamin Netanyahu aims to dismantle Iran’s nuclear and missile programmes, deemed existential threats.
Israel’s US ambassador, Yechiel Leiter, emphasized Fordo’s elimination as critical. Only the US B-2 Spirit, built by Northrop Grumman, can deliver the GBU-57, carrying up to 60,000 pounds (27,200 kg) with a 7,000-mile (11,000-km) range, extendable to 11,500 miles (18,500 km) with refuelling.
Trump, initially vague at the G7 Summit in Canada, decided within two days to engage, despite earlier suggesting a two-week deliberation period for potential talks with Iran.