Thousands of U.S. troops have been deployed to the Middle East amid the possibility of a ground operation to seize Iran’s Kharg Island, through which about 90% of Iran’s oil exports pass. Kharg, however, is only one of 10 Iranian islands in the Persian Gulf. According to CNN, others may be more critical for ensuring safe passage of ships — including military vessels — through the strategic Strait of Hormuz.
Seven of those islands — Abu Musa, Greater Tunb, Lesser Tunb, Hengam, Qeshm, Larak and Hormuz — form what researchers describe as Iran’s “arc defense.” In a 2022 study, Iranian and Chinese researchers wrote that three of them — Abu Musa, Greater Tunb and Lesser Tunb — are key to controlling the strait.
Footage from the strikes on Kharg
Because of the short distances between the islands and the shallow waters in much of the Gulf, large warships and tankers are forced to pass near these three islands. This could make them vulnerable to fast attack boats operated by the Islamic Revolutionary Guard Corps, naval mines or drones launched from the islands. Iranian officials have described these islands, along with others in the Gulf, as “unsinkable aircraft carriers.”
Last year, the Revolutionary Guard announced it was reinforcing its presence on Abu Musa, Greater Tunb and Lesser Tunb. “Our tactical approach requires us to arm and activate this group of islands. We have the capability to strike enemy bases, warships and assets in the region,” said IRGC Navy commander Alireza Tangsiri, who was killed this week.
If the United States seeks to seize Kharg Island, it would first need to neutralize Iran’s military positions on nearby islands to ensure safe passage for its naval forces. CNN military analyst Cedric Leighton said Thursday that Larak Island, located at the eastern entrance to the Strait of Hormuz, poses a particular challenge for vessels entering the Gulf. He described it as a critical military target, noting that Iran could effectively halt traffic through Hormuz from that location.
Carl Schuster, a former director of the U.S. Pacific Command’s Joint Intelligence Center, estimated that strikes on Iran’s Gulf islands could last between two days and two weeks and, if successful, would have significant impact. Speaking about Abu Musa, he said, “If you capture it and deploy radar and a small force, you can monitor activity in the strait.”
According to a March 24 report by the Institute for the Study of War, fighter jets struck Iranian military infrastructure on Abu Musa, Greater Tunb and Lesser Tunb during Operation Roaring Lion, including ports, warehouses and aircraft hangars. Schuster said such strikes are “the kind that precede an invasion.”
He added that if the islands were captured, a sizable force of about 1,800 to 2,000 troops would be needed to hold them and prevent Iran from retaking control — a significant risk, as U.S. forces stationed there could be exposed to Iranian attacks.
Schuster suggested it may be preferable to target Abu Musa, Greater Tunb and Lesser Tunb rather than Kharg Island. “That way there is less risk of harming the economy of a future government in Iran,” he said.