Iran says it’s deployed small submarines to act as an “invisible guardian” of the Strait of Hormuz amid a series of rejected peace deals between Tehran and the US.
The Islamic Republic has at least 16 of the Ghadir-class midget submarines, according to the International Institute for Strategic Studies. Each has a crew of fewer than 10 people and can carry either two torpedoes or two Chinese-designed C-704 anti-ship cruise missiles.
But they are noisy compared with most modern submarines, according to a person familiar with the matter, who requested anonymity because of the sensitivity of the matter. Their crews also have limited experience and the vessels are known to have maintenance issues, the person said.
Iran has effectively shut down the Strait of Hormuz, a strategic waterway through which about 20% of the world’s oil and liquefied natural gas used to travel, since the US and Israel first attacked on Feb. 28. Its decision to deploy the mini submarines, reported by the semi-official Tasnim news agency, came as US President Donald Trump told Fox News he was considering a revival of a plan to use the US military to escort ships.
Tehran has been able to exert control over Hormuz largely through the use, or simply the threat, of missiles and cheap drones, and the so-called midget submarines would likely serve a similar purpose.
One challenge when deploying them effectively is geography: the Strait of Hormuz is only about 100 meters deep at the most. The Persian Gulf is not much deeper. That makes it harder for submarines to hide, even when stationary, because active sonar can spot unnatural objects.
According to Tasnim, which is affiliated with the Islamic Revolutionary Guard Corps, the Ghadir is “specifically designed” for the waterway and its shallow depths.
None of the Islamic Republic’s submarines have made an appearance in combat during the war, and its only operational full-size sub — a Soviet-era Kilo-class boat — was sunk at the pier where it was moored.
Ghadirs are much smaller, displacing only 115 tons of water — a standard metric for submarines. Kilos, by contrast, displace more than 2,000 tons. US nuclear-powered Los Angeles-class attack submarines displace more than 6,000 tons.
Midget submarines are typically used for coastal defense, as they don’t have the endurance for long voyages and can’t submerge as deep as larger boats. Iran’s are domestically developed, with the first official announcement of production coming in 2005.
The Ghadirs are copies of North Korean designs, the person said.
The US and Israel have said nearly all of Iran’s navy has been destroyed, but small boats were reported to have attacked US ships transiting the strait twice in the past week.
US Central Command said they defeated multiple attacks against them. But commercial tanker traffic has remained largely choked off.
“Aside from the general deterrent factor, the primary risk would be minelaying,” said Emma Salisbury of the Foreign Policy Research Institute and the Royal Navy Strategic Studies Centre. “If I were Iran and wanted a big show, I’d use them in conjunction with fast-attack craft and drones for a big swarm attack on a US warship, but it depends how cavalier they want to be with the crews.”
Photograph: Oil tankers navigate the sea near Qeshm Island, Iran in the Strait of Hormuz on April 28, 2026; photo credit: Asghar Besharati/Getty Images
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