Opinion: Opinion | The Last Bet? What Trump's 'Mother Of All Bombs' Could Actually Do To Iran

On October 18, US President Donald Trump finally endorsed the candidature of Benjamin Netanyahu for re-election as Israel's Prime Minister, adding that they will soon finish the job together (defeating Iran). On the ground, however, despite the fact that there has been no direct exchange of strikes between the US and Iran over the past 30 days, the situation is far from stable. With each day, the number of vessels that Iran is striking in the Strait of Hormuz is rising sharply despite the US promising safe passage to ships through air escorts and security assurances. As per UK Maritime Trade Operations (UKMTO), which monitors the transit of ships across the Hormuz, more than 26 ships have been hit by Iran over the past two weeks, which includes at least three Very Large Crude Carriers (VLCC), which can typically carry up to 2 million barrels of oil. 

Surprisingly, the UKMTO admits that this figure may be grossly conservative, as not even 50% cases of ships being hit are being reported or recorded. In the past two weeks, ships have also been struck deep in the Gulf of Oman as well as off the coast of Qatar in the Persian Gulf. 

By doing this, Iran is not only displaying its ability to target ships beyond the Hormuz but is putting at risk the bypass formula for a safe and discreet method of transporting oil, increasing the risk and premium on the availability of ships. The US is, however, exercising restraint in firing back at Iran, more due to indecisiveness, coupled with the apprehension of an even stronger Iranian retaliation on its bases in the region if it strikes Iran.

On the other hand, the global energy crisis has flagged two important issues. Firstly, despite reports indicating that crude oil exports from the Gulf region (including the oil transported through pipelines in the Red Sea) in September rose to pre-war levels and even touched 22 million barrels per day, the prices remain high and are currently trading in the range of $109 per barrel. Secondly, the availability crisis of diesel is compounding the global energy crisis, both due to rising prices and scarcity in the market. Diesel is currently being sold in excess of $6.50 per gallon in the US, much higher than the sub-$4.0 before the Iran war. The diesel situation has forced US President Donald Trump to sign a deal with Russia to supply diesel to the US urgently. On October 16, he even waived off the sanctions, restrictions, and duties imposed on goods imported from Russia under the Lindsay Graham Act, which was passed by the US Congress on September 18.

The forthcoming mid-term elections in the US are compounding the problems for Trump as his approval ratings are plummeting due to inflation and a rise in fuel and food prices. This has fuelled speculation that the US may be forced to undertake one more swift and very punitive military campaign against Iran to force it to agree to American terms and open the Strait of Hormuz. Among the various options being discussed is the possible use of 'Mother of All Bombs' (MOAB).

The MOAB

The GBU-43/B Massive Ordnance Air Blast, or 'MOAB', is among the largest non-nuclear bombs ever developed. It weighs around 9,800 kg and was developed by the US to be used against Saddam Hussein's Iraq in 2003. It is a GPS-guided weapon, approximately nine metres long, and carries a massive explosive charge of around 8,500 kg, designed primarily to create a devastating blast over a wide area. It detonates above the ground, sending a powerful shockwave across its surroundings. It's a thermobaric weapon, which means it sucks in the atmospheric oxygen at the detonation site, creating an immense blast wave, high temperatures, and a massive vacuum effect that can destroy tunnels, caves, and fortified structures. Thermobaric bombs like these scatter the explosive fuel like an aerosol, making it possible for them to ignite the surrounding atmosphere.

An MOAB can also be used against exposed cave entrances to target personnel and positions in cave systems. However, it does not automatically destroy an entire underground complex. Blast pressure propagates into accessible openings, while debris and collapsing material can obstruct routes. Also, the effect inside a cave depends on the latter's geometry, depth, internal barriers, and ventilation. It is specifically configured to be delivered through a long-haul C-130 aircraft and has been used only once, against an Islamic State (IS) tunnel complex in Afghanistan's Nangarhar province, where it was reported that the strike killed at least thirty-six IS terrorists and destroyed tunnels and ammunition stores.

The Deep Penetrator GBU-57 Bomb

It may be recalled that the US had used twelve to fourteen GBU-57 bombs to 'obliterate' Iran's nuclear sites during the '12 Day War' in June 2025. There are four key differences between the two types of bombs.

• First, the GBU-57 penetration bombs are precision weapons that can precisely follow even a 32-inch crater caused by the first bomb (at least theoretically) to target deeply burrowed nuclear or weapon sites. The MOAB, in contrast, despite being guided by GPS, is not a precision but an area weapon.
• Secondly, the GBU-57 is delivered by B-2 Stealth bombers, which are fast-moving and are able to deceive enemy radars. In contrast, MOAB is delivered by C-130 aircraft, which are large in size and slow-moving, thus prone to interception.
• Third, unlike GBU-57, which is configured for deep bunker bursting, the MOAB cannot penetrate deep into the Earth but causes damage due to the explosion and incendiary effect caused over a large area on the surface.
• Fourth, the MOAB, due to its characteristics, has a greater psychological impact and greater coverage area as compared to GBU-57, and can thus cause a mass casualty event if dropped over a dense population centre.

Can It Deliver The Knock-Out Punch For Trump?

The US is stuck in the Iran war because it has not been able to defeat it militarily or economically, nor has it succeeded in opening the Strait of Hormuz. If Trump is considering the use of an MOAB to destroy the already ‘obliterated' nuclear sites in Iran, then it's not a great idea, because the MOAB does not have the technical capabilities to penetrate the surface deep enough to do so. Can it destroy Iran's deeply buried weapon site in the Pick-Axe Mountain? The answer is again ‘No', as it is deeply buried inside a mountain, almost 300 feet under, if not more.

Can an MOAB deliver a decisive blow to Iran that may force it to surrender immediately, as Japan did after Hiroshima and Nagasaki in World War 2? Although there are no clear estimates, even if an MOAB can destroy everything in an area of 2 sq. km, it means that, as per the average population density figures in Iran, 100-150 people could be killed in any area, and in a densely populated neighbourhood of Tehran, this could go up to 20,000 to 25,000 people.

Will Iran surrender if it suffers such losses? Will its state machinery collapse if an MOAB actually succeeds in causing such massive destruction? For a large country, 1700 km x1800 km large with a diverse terrain and topography and with a population of over 90 million, which had earlier suffered losses of over 1 million lives in the war against Iraq in the 1980s, it is an unlikely presumption.

On the contrary, Iran will then be free to unleash whatever it has in its weaponry, overt and otherwise, not only over US bases in the Gulf region, key energy and power infrastructure, but also against Israel and even some assets in Europe. Houthis may be prompted not only to intensify their campaign against the Saudis but also to shut down the other vital chokepoint, Bab-al-Mandeb in the Red Sea, for all ships, further intensifying the global energy and trade crisis. The threat of undersea cables in the Persian Gulf being targeted by Iran also cannot be discounted, a step that may virtually cripple the global high-speed data connectivity system. Plus, after such a devastating effect, Iran may not only withdraw from the Non-Proliferation Treaty but also expedite its efforts towards building a nuclear weapon, a step that may irreversibly alter the security landscape of the entire region.

The US is trapped in a war it is finding it difficult to exit. Reports from the US Congress research committees highlight the amount of damage suffered by the US in the Iran war, with more than 81 aircraft damaged and over $38 billion spent in direct costs. Plus, the depleted inventory of key missiles and interceptors like the Patriot, THAAD, and Tomahawk means that not only are American bases vulnerable to increased success of Iranian attacks, but the resupply of these key missiles may take months, if not years.

With mid-term elections looming, the fear of a loss of mandate may put an end to all of Trump's plans and ambitions. In Israel, too, which has been riding on US support in fighting the war, the elections to the Knesset are a fight for survival for Netanyahu.

Under such circumstances, triggering a renewed spell of conflict may be an act of desperation rather than conviction, with no guarantee of success. The deliberately planted leaks of the possibility of using an MOAB may be more about testing the waters. With its vast geographical expanse and a determined regime fighting for survival, it is unlikely that a bomb or two will bring Iran to its knees. A nuclear bomb, in the garb of a thermobaric bomb like the MOAB, may, however, be a different proposition. But then, the consequences of it may be equally devastating, if not more. For the time being, an MOAB, like the previous threats of sending Iran "back to the Stone Age" or landing troops on the Kharg Island - or an attack on the Pick-Axe Mountain site - remains just rhetoric.

(Col Rajeev Agarwal is a foreign policy and security expert and author of 'Between Tehran and Tel Aviv: Gaza's Story of Unending War')

Disclaimer: These are the personal opinions of the author