Trump Rules Out Nuclear Weapons Against Iran

US President Donald Trump has for the first time explicitly ruled out the use of nuclear weapons against Iran, but did not deny US media reports that his administration is considering deploying America's most lethal non-nuclear munition, nicknamed the "mother of all bombs", in the period ahead.

In an interview published by right-wing US outlet Newsmax on Thursday, Trump implied there were no plans to use nuclear weapons, while making clear that the devastating aerial weapon GBU-43/B Massive Ordnance Air Blast Bomb — known as MOAB, or the "mother of all bombs" — "is not a nuclear weapon".

"I will not use nuclear weapons. We don't have to do that. We are the greatest nuclear power in the world," he told Newsmax.

The remark marks the first time Trump has made a definitive statement on the nuclear question, following speculation about the possibility of atomic conflict in the early phase of the US and Israeli war against Iran. It also appeared to confirm speculation that a new phase of the war is approaching, possibly after the US midterm elections on November 3.

What did Trump say?

Trump told Newsmax that the US would likely carry out further airstrikes targeting Iran's nuclear facilities, particularly at Pickaxe Mountain, where Tehran is believed to be hiding a nuclear site deep beneath layers of granite.

He ruled out the use of nuclear weapons or tactical nuclear weapons.

"I will not use nuclear weapons. We don't have to do that. We are the greatest nuclear power in the world," he said.

He also made clear that the MOAB, which CNN reported the US government is considering using, "is not a nuclear weapon".

Asked whether the MOAB was a "tactical nuclear" device — referring to smaller nuclear munitions — Trump repeated that it was not.

"The mother of all bombs is not a nuclear weapon. It's not a nuclear weapon at all. It's just a very big bomb," Trump said.

Trump declined to say whether he had authorised the use of the bomb in Iran.

Trump also implied that further strikes could come in the near future. He argued the US could not end the war at this point because it had to ensure Iran could not produce nuclear weapons, saying he believed "if they have it, they'll use it immediately, in my opinion".

Trump also repeated that the war would end "very soon", whether by force or diplomacy, and that oil prices would then fall.

Asked whether he would send "boots on the ground" into Iran, Trump said: "No, I don't see that, I don't see it." Earlier in the war, Trump had made remarks about deploying troops, a move analysts said would cause heavy losses for US soldiers given Iran's mountainous terrain.

What is the "mother of all bombs"?

The MOAB carries a warhead of about 8,500kg of high explosives. The bomb weighs 9,800kg, roughly equivalent to four cars, and is more than 9 metres long. Stealth bombers are too small to carry it, so it must be deployed by the larger Lockheed C-130 Hercules transport aircraft.

According to experts who spoke to Al Jazeera, the bomb is designed to detonate several metres above the ground, creating intense fireballs capable of destroying buildings and hard surface structures within a 1km radius. The US Air Force has said the bomb is so powerful that during tests, a mushroom cloud from the explosion was visible from about 32km away.

"Its large explosive charge can create a devastating shock effect on people, equipment and vulnerable structures," said Elijah Magnier, a Brussels-based military and weapons analyst. "Its purpose is to create an extremely powerful explosion over a surface area."

However, Magnier said there were doubts about whether using this massive surface-blast bomb would be effective against Iran's deeply buried nuclear facilities. He added that Iran's terrain could make it difficult for large transport aircraft to approach.

What has Trump said about nuclear weapons before?

Trump has never explicitly mentioned using nuclear weapons, but he has also never ruled it out.

Speculation about whether Washington might use nuclear weapons spread widely in the early days of the conflict, largely due to the extreme nature of many of Trump's threats against Tehran.

In April, when Iran imposed a shipping blockade in the Strait of Hormuz, Trump posted on Truth Social that "a whole civilisation will die tonight, never to return" if Iran did not agree to a peace deal and reopen the strait.

He also threatened to destroy Iran's infrastructure, saying a bombing campaign "will be Power Plant Day and Bridge Day, combined, in Iran".

Experts largely interpreted his remarks as threats of nuclear destruction, but they still failed to force Iran to the negotiating table.

Although Trump largely moved away from the muscle-flexing rhetoric in the weeks that followed, he repeated at the United Nations General Assembly in New York last month that he could "wipe out" Iran. He also told the assembly he believed a deal would emerge after the midterm elections.

What are "tactical" nuclear weapons?

"Tactical" nuclear weapons are smaller nuclear munitions designed for the battlefield, as opposed to strategic nuclear weapons designed for wide-scale destruction.

Some argue tactical nuclear weapons have a smaller impact than atomic bombs, but experts warn the name is misleading and that they can still be devastatingly destructive. Their yields, ranging from 0.3 to 50 kilotons, can affect an area within a 500-600km radius.

The US once dropped a 15-kiloton nuclear bomb on Hiroshima, meaning that weapon today would be classified as a tactical nuclear weapon. The US, North Korea and Russia have tactical nuclear weapons in their arsenals, though no country has ever used them. Tactical nuclear weapons are not covered by any international treaty and are largely unregulated.

How might a new US attack on Iran unfold?

With Trump not ruling out dropping the MOAB, analysts speculate the US could open another intense — possibly final — bombing campaign targeting Iran's nuclear and defence facilities, especially Pickaxe Mountain.

The US could also continue its naval blockade of Iranian ports while escorting commercial ships through the Strait of Hormuz.

Iran has said it will retaliate against escalating attacks by targeting oil and digital infrastructure in neighbouring Gulf states.

Senior defence officials have also warned Iran would invade its neighbours if the US launched a ground campaign, though Trump appeared to have ruled that out.

Earlier in the war, he had hinted at the possibility of sending ground forces to recover about 400kg of "yellowcake" — highly enriched uranium that Washington and Israel accuse Tehran of hiding underground.

Trump's calls in March with Kurdish militia groups fighting against Iran fuelled speculation that Washington might coordinate with them for an invasion, though that did not happen.