Reports on Friday that the United States was ordering an additional round of 30,000-pound (13,600-kilogram) mega bunker buster bombs, known as the Massive Ordnance Penetrator (MOP), on an emergent basis raised the issue anew of whether the American military possesses the capability to end Iran’s nuclear program, should it decide to attack.
There are at least two avenues from which to analyze the question.
One is the fact that Washington is ordering new mega bunker buster bombs for the first time in years without carrying out a standard competitive bidding process.
The second is multiple differences between the defensive situation at Pickaxe Mountain, the largest remaining Iranian nuclear facility, which lies underneath a mountain, versus that at Fordow, the Islamic Republic’s key nuclear facility under a different mountain, which the US bombed with 12 MOPs in June 2025.
Regarding the US military ordering new bunker busters, there are positive and negative points.
The positive points are that the US did not issue such orders immediately after June 2025 and that the orders are for these same bombs, and not for some new larger bomb that has yet to be developed.
Had the American military ordered additional such bombs immediately after June 2025, this could have been a concern that there were not enough even for one more similar operation – such as what might be necessary against Tehran now.
Moreover, if instead of ordering the same MOPs, Washington were ordering new 40,000-pound (18,144-kg.) bombs, there could be greater concerns that the MOPs were viewed as inadequate for the future.
On the negative side, the act of ordering itself, just as the US may strike Iran, suggests that the number of MPs in inventory is significantly limited. This same problem is accentuated by the rushed order situation.
New round of MOPs to be delivered in 2028
That said, the new round of MOPs will only be delivered in 2028.
Unless the US has planned extremely poorly, the fact that the American military is fine with waiting another two years suggests that it has plenty of MOPs in stock to strike Iran in any potential imminent conflict over the nuclear and other threats.
Regarding the differences between the nuclear facility under Pickaxe Mountain near Natanz and the nuclear facility which was under the Fordow mountain, the Natanz mountain is about 650 meters high, or well over 50% higher than Fordow, potentially providing even greater protection from an aerial attack.
Also, a recent report by the Institute for Science and International Security stated that satellite footage has shown that the nuclear facility near Natanz has only one ventilation shaft, whereas the Fordow nuclear facility had at least two.
In fact, US Chairman of the Joint Chiefs of Staff Gen. Dan Caine explained, in a press briefing in June 2025, that the entire US aerial strike strategy for the 12 MOPs it dropped at Fordow revolved around those ventilation shafts.
A series of MOPs were dropped; first to destroy covers which the Iranian had placed on the shafts, and then to enter the shafts to penetrate deep underground into the heart of the nuclear facility.
One thing that has remained unclear in all of this is how deep the MOPs actually need to penetrate to permanently disable a nuclear facility.
The mountain on top of the Fordow facility is about 960 meters tall.
As impressive as it is, the MOP, with its steel casing and delayed fuse capabilities, is still only designed to penetrate an estimated 60 meters (200 feet) through rock or other dense substances before detonating.
Put bluntly, the MOP would have been totally inadequate to penetrate through and under the mountain to the Fordow nuclear facility.
It would seem to be even more inadequate to penetrate the facility under Pickaxe Mountain at a height of 1608 meters above sea level.
Yet, Iran has admitted that its Fordow facility is no longer usable and has made no progress in rebuilding this gem of its nuclear program over eight months, signaling that the plan to drop MOPs repeatedly through the two tunnel shafts did the job.
Institute for Science and International Security President David Albright has warned of Iran burying and reinforcing its tunnels and entrances at Pickaxe Mountain, at the Isfahan nuclear facility, and at the Taleghan 2 nuclear facility.
Albright suggested that US military officials could be as creative about finding vulnerabilities as they were in attacking Fordow.
He explained that thermobaric bombs may be used effectively against underground nuclear facilities, since they are generally more effective when used in enclosed spaces such as tunnels, buildings, and bunkers.
Once a thermobaric bomb strikes its target and detonates, the bomb’s container opens and disperses a fuel mixture as a cloud. Next, the typical blast wave of a thermobaric weapon continues substantially longer than standard explosives.
One problem is that Tehran has already witnessed a lot of Israeli and American surprises during the June 2025 attack, and has a clearer understanding of what the weapons damaged, at which depths, and how they did so, as well as what they failed to damage.
In that sense, the question of whether the US can destroy the Pickaxe Mountain nuclear facility near Natanz will not only be a size-of-bunker-buster arms race but also an intelligence race of who can outwit whom, matching offensive and defensive capabilities.