The June 21 strike on Fordow was designed with extraordinary precision.
- Operation Midnight Hammer was a 15-year US effort to develop weapons for Fordow strike
- Fordow is half a mile inside a mountain and was identified by US intelligence in 2009
- The GBU-57 Massive Ordnance Penetrator was developed to destroy hardened underground targets
The American strike on Iran's Fordow nuclear enrichment facility was the outcome of a covert, 15-year-long military effort to develop specialised weapons capable of reaching the deeply buried site, according to Chairman of the Joint Chiefs of Staff, Lt. Gen. Dan Caine.
The revelations, as reported by The New York Post, offer an insight into the Pentagon's long-term planning and technological development in response to the Iranian nuclear threat.
Caine referred to the operation as "Operation Midnight Hammer," saying it "was the culmination of those 15 years of incredible work, the air crews, the tanker crews, the weapons crews that built the weapons, the load crews that loaded it."
Fordow, located roughly half a mile inside a mountain, came to the attention of US intelligence agencies in 2009. Soon after, defence experts determined that no existing weapon in the US arsenal could effectively destroy it.
Caine told The New York Post that officials, along with a Defense Threat Reduction Agency (DTRA) officer, concluded that the US lacked a weapon capable of effectively striking and neutralising the target.
This sparked the classified development of the 30,000-pound GBU-57 Massive Ordnance Penetrator (MOP), a powerful bunker-buster bomb. Designed to neutralise hardened underground facilities such as Fordow, the MOP represents one of the most technically complex munitions ever constructed by the US.
Caine described the broader scientific endeavour behind the weapon's design. He said, "Weaponeering is the science of evaluating a target... Ultimately, weaponeering is determining the right weapon and fuse combination to achieve the desired effects and maximum destruction against a target."
He explained how the DTRA team analysed Fordow's structure to identify which elements would need to be destroyed to neutralise its function. The scale of effort behind the project was immense. "We had so many PhDs working on the MOP programme doing modelling and simulation that we were - quietly and in a secret way - the biggest users of supercomputer hours within the United States of America," Caine said.
The Pentagon, in partnership with private industry and tactical experts, spent years refining the weapon.
The GBU-57, exclusively deliverable by B-2 stealth bombers, stands as the most powerful bomb in the US military's inventory. Built with a steel casing, high explosives and a programmable fuse, each unit is tailored to produce a specific impact within its intended target. "Each weapon had a unique desired impact, angle, arrival, final heading and a fuse setting," he added. "The fuse is effectively what tells the bomb when to function. A longer delay in a fuse, the deeper the weapon will penetrate and drive into the target."
The June 21 strike on Fordow was designed with extraordinary precision, benefiting from over a decade of intelligence gathering and simulations. Pentagon planners focused on hitting two key ventilation shafts, which were critical to reaching the plant's core.
Caine told The New York Post that Iran tried to block the ventilation shafts with concrete to stop an attack, but US planners had already prepared for this. The first bomb broke through the concrete and uncovered the main shaft. In total, four bombs penetrated the facility through the main exhaust shaft, moving "down into the complex at greater than 1000 feet per second and explode in the mission space."
