Iran Deploys Mines in Strait of Hormuz as U.S. Struggles to Counter Threat

Iran has begun laying mines in the Strait of Hormuz, through which 20% of the world's oil shipments pass.

The New York Times reported on the 13th (local time), citing U.S. officials, that while U.S. forces destroyed an Iranian large minelaying vessel, Iran began deploying mines using small boats starting on the 12th. The NYT added that Iran's Islamic Revolutionary Guard Corps (IRGC) could deploy hundreds, potentially thousands, of small vessels. British Defence Secretary John Healey also stated on the 12th that "it is highly likely Iran has begun laying mines in the strait." The Institute for the Study of War (ISW), a U.S. think tank, previously estimated that Iran has already deployed 10 mines.

The Wall Street Journal noted that Iran is using small boats indistinguishable from fishing vessels and unofficial militia including divers to lay mines, making identification and removal virtually impossible for U.S. forces. The U.S. Defense Intelligence Agency (DIA) estimated that Iran possessed more than 5,000 mines as of 2019.

Experts warn that once mines are deployed en masse, removal is virtually impossible before the war ends. Caitlin Talmadge, a political science professor at MIT, said, "Mine clearance is an activity possible during peacetime. During war, the ships and helicopters performing this task become extremely vulnerable to enemy attack." The Strait of Hormuz is only about 34 kilometers wide at its narrowest point, significantly increasing the likelihood of merchant ships contacting mines.

Iran's new Supreme Leader Ayatollah Seyyed Mojtaba Khamenei emphasized in his first official statement on the 12th that "we must continue to use the leverage of blocking the Strait of Hormuz." Beyond mines, four merchant ships attempting to pass through the strait in the past two days have been attacked by projectiles believed to be drones and missiles. Iran possesses the capability to threaten strait passage with combined asymmetric forces including mines, drones, explosive unmanned vessels, and land-to-ship missiles.

U.S. mine-clearing capabilities also face a gap. The U.S. military retired its last minesweeper from the Middle East last year and established a policy to transition to unmanned surface vessel systems. However, concerns have emerged about operational gaps as existing minesweepers were retired before the new system's combat capabilities were verified. As President Trump emphasizes merchant ship passage through the strait, securing actual transit safety has emerged as America's most urgent challenge.