The U.S. Department of Defense revealed new details about the American airstrikes on Iran’s nuclear facilities on Thursday, describing a 15-year effort to knock out the hardened, underground site at Fordow.
Gen. Dan Caine, chairman of the Joint Chiefs of Staff, told reporters that Pentagon planners developed the GBU-57 Massive Ordinance Penetrator to carry out the attack.
“In 2009, a Defense Threat Reduction Agency officer was brought into a vault at an undisclosed location and briefed on something going on in Iran,” he said. “He was shown some photos and some highly classified intelligence of what looked like a major construction project in the mountains of Iran.”
Caine said that the officer and his teammate “literally dreamed” about striking the nuclear plant even as they had to conceal their work from family and friends.
“For more than 15 years, this officer and his teammate lived and breathed this single target, Fordow, a critical element of Iran’s covert nuclear weapons program,” Caine said.
“He watched the Iranians dig it out. He watched the construction, the weather, the discard material, the geology, the construction materials, where the materials came from,” he said. “He looked at the vent shaft, the exhaust shaft, the electrical systems, the environmental control systems, every nook, every crater, every piece of equipment going in and every piece of equipment going out.”
That study culminated in the development of the 30,000-pound “massive ordinance penetrator,” frequently referred to as a bunker buster.
“In the beginning of its development, we had so many Ph.D.s working on the MOP program, doing modeling 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.
Since the attack on Saturday, U.S. and Israeli government agencies have begun efforts to analyze whether the strike knocked out the plant entirely or if it might only have been temporarily damaged.
On Wednesday, The New York Times and other news outlets published the results of a “low confidence” U.S. Defense Intelligence Agency report assessing that the facility had sustained “moderate to severe damage,” but that Iran’s overall nuclear program might only have been delayed by a matter of months.
U.S. Secretary of Defense Pete Hegseth told reporters that he was furious about the leak of that initial report and slammed reporters for publishing it, saying that its conclusions were misleading.
“Every outlet has breathlessly reported on a preliminary assessment from DIA,” Hegseth said. “It was preliminary, a day-and-a-half after the actual strike.”
“Again, this is preliminary. Leaked because someone had an agenda to try to muddy the waters and make it look like this historic strike wasn’t successful,” he said.
The Trump administration has threatened to sue the Times over the leak, insisting that Iran’s nuclear facilities were devastated in the attack.
An attorney for the Times wrote to U.S. President Donald Trump’s lawyer on Thursday rejecting his demand for a retraction.
“No retraction is needed. No apology will be forthcoming,” wrote David McCraw, the paper’s deputy general counsel. “We told the truth to the best of our ability. We will continue to do so.”
