The head of the US Joint Chiefs of Staff, Gen. Dan Keene, said on Thursday that the US strike on Iran's Fordow nuclear enrichment facility on Saturday took 15 years to prepare, revealing that the heavy bombs used were specifically designed for the underground facility, according to the “New York Post“.
The US first learned of the existence of the Fordow facility, located about a half-mile from the base of a mountain, in 2009.
Keene said that officials and an officer from the Defense Threat Reduction Agency (DTRA) determined that the US did not have “a weapon capable of striking and sufficiently destroying that target“.
So they began building underground penetration bombs of the “GBU-57“ type weighing 30,000 pounds, while ordinary Americans had no idea of the threats posed by Tehran.
“Weapons is the science of target assessment...
Ultimately, it is determining the appropriate combination of weapon and detonator to achieve the desired effects and maximum destruction of the target... At Fordow, the DTRA team understood with great confidence what elements of the target were needed to disrupt its functions, and the weapons were designed, planned, and delivered to ensure that they would achieve the desired effect in the mission area“.
At one point, Keene added, “we had a large number of PhDs working and doing modeling and simulations, to the point that we were (secretly and quietly) the largest user of supercomputer man-hours in the United States“.
The Pentagon works with industry and other tactical experts to develop the GBU-57 bomb, which can only be dropped by B-2 bombers, and tested it “multiple times“.