B61-11: The bunker-buster Israel can't get from Washington

The United States maintains hundreds of nuclear warheads in its active arsenal. Only one was designed from the outset for a singular mission: to penetrate deep into the earth and turn the rock itself into a weapon of destruction. This is the B61-11, the only nuclear weapon in the American operational inventory built to destroy deeply buried bunkers.

While most nuclear bombs are designed to detonate in the air or on the surface, the B61-11 is meant to drive into the ground and generate a massive seismic shockwave inside the earth, a kind of artificial earthquake that collapses tunnels and deep facilities without striking them directly.

According to American reports, the administration in Washington has examined military options against a particularly fortified Iranian underground nuclear facility known as "Pickaxe Mountain," near Natanz. The facility is carved 100 meters deep into solid granite rock.

Military analysts note that even the most powerful conventional bunker-buster in the US arsenal, the 13.6-ton GBU-57 MOP, would struggle to completely destroy a structure at that depth. The B61-11 theoretically could.

US Marines launch the F-35C (Photo: US CENTCOM)

Variable yield and penetration capability

The bomb is a dial-a-yield weapon. Its maximum yield is estimated at 340 to 400 kilotons, 20 to 25 times the power of the bomb dropped on Hiroshima. It is designed for delivery by strategic bombers, primarily the B-2 Spirit stealth bomber.

The exact number of units is classified. The strategic significance is clear: the United States has enough nuclear bunker-busters in its arsenal that can, at least on paper, totally destroy deep underground facilities, destruction that would be extremely difficult to recover from for decades.

According to a CNN report, the US military has developed comprehensive strike plans against Iran, including possible use of the GBU-43/B, known by its nickname "Mother of All Bombs" (MOAB). President Donald Trump ordered the military to prepare varied strike packages against Iran, including hits on "many energy infrastructures" and key nuclear sites.

Despite the "earth-penetrating" designation, the bomb penetrates only a few meters, about 3 to 6 meters, into the ground or rock. The great advantage is 'shock coupling': transferring the explosion's energy directly into the earth rather than wasting it in the air. The result is a massive seismic shockwave that collapses deep tunnels and bunkers.

However, American military sources have raised doubts about the MOAB's ability to penetrate granite rock at depth. The plans presented explicitly call for using the MOAB to destroy the "Pickaxe Mountain" facility, but professional assessments indicate that the B61-11 nuclear bomb is the only one that might be capable of doing so.

The end of American military aid to Israel

Parallel to the renewed interest in the American nuclear bomb, a dramatic shift has occurred in security aid relations between Washington and Jerusalem. This week President Donald Trump announced that the US would halt the annual aid package of approximately four billion dollars by year's end.

According to him, this was agreed with Prime Minister Netanyahu, based on the claim that Israel "no longer needs it." The immediate implications are not necessarily a complete halt to weapons supply, Trump emphasized that Israel would be able to continue purchasing, but rather a change in the financing structure and procurement preferences.

A large portion of the aid was designated for purchasing American systems, including precision munitions and bunker-busting bombs. Stopping the grants could accelerate local development, increase reliance on direct procurement, or change the IDF's priorities regarding heavy armament against fortified targets.

Israel possesses a variety of conventional bunker-busting bombs, some American-made and some Israeli, and has used them successfully against tunnels and fortified structures. But there is no verified public information about the existence of an Israeli weapon equivalent to the B61-11. Assessments by international research organizations do not indicate the existence of a dedicated nuclear earth-penetrating warhead in the Israeli arsenal.