As tensions escalate between Israel and Iran, there is growing speculation about the United States' potential military involvement in the conflict. Should the U.S. engage, a primary objective would likely be to target and neutralize Tehran’s underground nuclear facilities that are crucial for enriching nuclear material. This critical mission could rely heavily on a select group of Air Force strategic bombers equipped to deploy 30,000-pound precision-guided bombs, specifically designed to penetrate and destroy fortified subterranean targets.
The bomb most suited for this operation is the GBU-57, commonly referred to as the “bunker buster” or the Massive Ordnance Penetrator (MOP). Named aptly for its specialized design, the MOP is engineered to effectively strike deeply buried and fortified facilities, such as underground bunkers and tunnels. Its heavy construction and steel alloy composition allow it to penetrate significant depths before detonating, making it a strategic asset for the Air Force.
Despite being the heaviest conventional weapon in the U.S. arsenal, the MOP is not designed for widespread destruction. Instead, military commanders depend on its GPS-guided precision to hit specific, well-defended targets that conventional bombs may not effectively reach. While there are no public records of the MOP's deployment in combat scenarios, experts estimate its capabilities have advanced over the past two decades, with penetration abilities potentially exceeding 200 feet.
The only aircraft in the U.S. Air Force capable of deploying the MOP is the B-2 Spirit stealth bomber. Currently, there are 19 operational B-2s, which are renowned for their long-range capabilities and midair refueling options. For instance, during the Kosovo War in the late 1990s, B-2 pilots executed extensive missions, traveling from Whiteman Air Force Base in Missouri to strike high-value targets. Additionally, in 2017, a duo of B-2s undertook a remarkable 34-hour flight to target Islamic State camps in Libya.
Recent advancements in MOP technology include the resolution of an unspecified “integration issue” associated with the B-2. The Air Force has also been experimenting with innovative technology that enhances target destruction, particularly in scenarios where detailed intelligence is scarce. One such improvement is a smart fuse that can detect voids or cavities in its descent path, allowing for optimized detonation. This capability could be crucial if military commanders deem it necessary to strike the same deep target multiple times.
Among the most significant potential targets is Iran's Fordow nuclear facility, situated in the desert southwest of Tehran. This facility is entirely underground, carved into a mountainside, and reportedly features tunnels with reinforced walls and blastproof doors. According to U.N. inspectors, some bunkers at Fordow are protected by as much as 300 feet of rock. Although Fordow is officially designed to produce uranium enriched to 20 percent purity, recent reports from the International Atomic Energy Agency (IAEA) indicate that Iran has ramped up its production of uranium enriched to 60 percent—much closer to the 90 percent threshold necessary for nuclear weaponization.
Experts caution that even a successful strike on the uranium-enriching centrifuges at Fordow would not necessarily dismantle Iran's nuclear ambitions. There could be other undisclosed enrichment sites or caches of nuclear fuel that remain unknown to U.N. inspectors, as highlighted by Richard Nephew, a former U.S. negotiator with Iran. “Even if Fordow was evaporated tomorrow, we would still have massive concerns,” Nephew stated.
Despite the ongoing tensions, initial waves of Israeli attacks have not resulted in irreversible damage to Iran's nuclear facilities, as indicated by statements from both nations and corroborated by satellite imagery. While Israel targeted areas near Fordow, the main underground facility itself was reportedly not struck. Attacks on Natanz, another primary enrichment site, did inflict damage, disrupting several facilities and the electrical systems, according to reports from the IAEA and nonproliferation analysts.
Recent analyses reveal that the underground enrichment machinery at Natanz may have sustained damage contrary to earlier assessments. The IAEA confirmed direct impacts on the underground enrichment halls at Natanz. Other facilities, including a uranium metal production site in Isfahan, a military complex in Parchin, and the Arak heavy water reactor, have also been reported as targets of Israeli strikes, though the Bushehr nuclear power plant was not affected.
