Can Trump’s ‘gunboat diplomacy’ stop Iran from blocking the flow of oil? Not likely, say experts

With jagged cliffs rising from the Arabian Sea, the Strait of Hormuz is striking in its scenery — and these days, its emptiness. This resource superhighway, which normally hosts more than a hundred of the world’s largest oil and liquid natural gas (LNG) tankers every day, has seen no more than a handful all week.

They are the brave ones, daring to run these front lines where U.S. and Iranian naval forces face off. At least 14 commercial vessels have suffered some kind of violent incident, leaving at least eight mariners dead. 

Oil and gas facilities have been hit, too. Smoke still rises from burning fuel tanks at Oman’s Port of Salalah.

Iran, which commands one side of the narrow waterway, has declared it closed, labelling any vessel destined for the U.S., Israel or their “hostile partners” a “legitimate target.”

A fifth of the world’s oil and LNG runs through the Strait of Hormuz, leaving customers worldwide facing shortages and rising prices due to the blockade. Iran has predicted oil will surpass $200 US a barrel, double its current levels and well above pre-war levels of $72. 

This, despite a record intervention from the International Energy Agency, attempting to soften the blow. The IEA, made up of major oil-consuming countries, recommended releasing 400 million barrels from global strategic reserves.

“The United States completely blew this,” said Sal Mercogliano, a naval historian and maritime shipping expert at Campbell University in North Carolina. “How they didn’t know this was going to happen is really mystifying … they should have been prepared.”

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U.S. President Donald Trump has dismissed the problem as temporary, and the danger as manageable. He says he told oil companies “they should” continue to use the sea lanes, offering them better insurance. He promised to check Iranian forces in the Strait of Hormuz by “taking it over,” if necessary.

Trump is counting on his own forces — “the most powerful military in the world” — to prevail. He’s already boasted of destroying all of Iran’s navy, including 28 mine ships, and that the U.S. “just took out just about all of their mines,” without offering any evidence. 

“It’s all very much gunboat diplomacy,” said Mercogliano, reminiscent of colonial power bullying from the 1800s.

Maritime guerilla warfare

The Strait of Hormuz is only 60 metres at its shallowest, and 33 kilometres at its narrowest, with shipping lanes no more than two kilometres wide.

Naval experts like Mark Norman, a retired vice-admiral of the Canadian navy and a former vice-chief of Canada’s defence staff, are skeptical the U.S. can re-establish shipping through the area. 

“It can be pretty impressive to go in there and basically pummel the hell out of command and control, infrastructure, leadership, military and industrial capability, et cetera,” he said. “But that’s not a guarantee of anything.”

The challenge comes in the form of asymmetrical warfare, say experts. 

The U.S. is fighting with a limited number of large, expensive vessels — two aircraft carrier groups and additional destroyers and submarines. 

Iran’s traditional navy has suffered heavy losses in the Strait of Hormuz and, in one case, the Indian Ocean. But the Iranian Revolutionary Guard’s other weapons are “the more dangerous threat to shipping,” said Justin Crump from Sybilline, a British risk and intelligence consultancy.

He lists fast, well-armed speedboats and land-based anti-ship cruise missiles, which have already been fired at the USS Abraham Lincoln, an American aircraft carrier.

Norman calls Iran’s approach maritime guerrilla warfare.

Mines, he says, remain the most lethal weapon in Iran’s arsenal, and likely the biggest threat to commercial ships as well as U.S. naval vessels.

He says many of them could have been placed in the Strait of Hormuz long before the current conflict broke out, programmed to explode when a certain type of ship is detected or even triggered remotely. 

The mines are relatively cheap yet can do damage to warships in the millions or even billions, if they manage to sink them. 

Perils of escorting tankers

In 1988, the frigate USS Samuel Roberts hit an Iranian mine in the Persian Gulf. The mine reportedly cost $1,500 US to make, while the damage to the ship cost $96 million to fix.

That’s the risk of having large U.S. naval ships like destroyers escort tankers through the strait, as Trump promised — and his navy rejected as too dangerous for now. U.S. Energy Secretary Chris Wright says escorts could start by the end of March.

Destroyers don’t have any special ability to clear mines and can be just as vulnerable to them as the commercial vessels they’re protecting.

If a ship does hit a mine in the strait — or is sunk by a missile — it can block the waterway for days or weeks.

“It actually doesn’t take a lot to wreak havoc in a very tight piece of water like this,” said Norman. 

The Houthi rebels, a militant Iranian proxy group based in Yemen, posed a similar threat to the narrow entry into the Red Sea, launching attacks on shipping from 2023 until 2025 and scaring away commercial traffic. It was protesting Israel’s assault on Gaza.

The U.S. and other countries launched military action against the Houthis, including air strikes on bases and airports in Yemen. But the only solution turned out to be a negotiated deal between the Houthis and the Americans last May, which ended the attacks.

Experts like Mercogliano say it may take a ceasefire and diplomatic agreement between Iran and the U.S. to keep the Strait of Hormuz open. 

“Without putting troops on both sides of the Strait of Hormuz and ensuring that you’re able to prevent drones and mine attacks, I just don’t see a military solution,” he said.