The United States military says its warships will conduct an operation to clear mines laid by Iran in the Strait of Hormuz.
In a statement released on Saturday, Central Command (CENTCOM), which has responsibility for US military operations in the Middle East, said the mission would be undertaken by guided missile destroyers USS Frank E Peterson and USS Michael Murphy and would aim to establish a “safe pathway” for the free flow of global commerce after Iran’s near-closure of the waterway since the war the US and Israel launched on Iran on February 28.
On Wednesday after the announcement of a two-week ceasefire to allow for talks between the US and Iran, Iran’s Islamic Revolutionary Guard Corps (IRGC) released a map of the Strait of Hormuz showing what it said was a safe route for ships to follow through the strait.
The map appears to direct ships farther north towards the Iranian coast and away from the traditional route closer to the coast of Oman.
In a statement, the IRGC said all vessels must use the new map for navigation due to “the likelihood of the presence of various types of anti-ship mines in the main traffic zone”.
The stakes are high. One-fifth of the world’s oil and liquefied natural gas (LNG) supplies had been shipped through the Strait of Hormuz before the war. Even a single mine, experts said, is enough to compel operators to assume a wider threat, in effect invalidating insurance and shutting down their use of the waterway.
What are sea mines, and how do they work?
Naval mines have been described as the most cost-effective weapons in modern warfare. According to an analysis by the Philadelphia-based Foreign Policy Research Institute (FPRI), sophisticated modern mines can be manufactured for tens of thousands of dollars, yet they can impose economic and strategic costs that are orders of magnitude higher.
Iran’s stockpile is estimated by maritime analysts to number 2,000 to 6,000 mines, a significant portion of which are produced domestically. These weapons generally fall into three categories, based on how they interact with their targets:
- Contact mines: These are traditional designs, such as the M-08, which date back to World War I. They are moored to the seabed and detonate upon physical contact with a ship’s hull.
- Bottom (influence) mines: Models like the Maham-2 rest on the seafloor and are triggered by the acoustic, magnetic or pressure signatures of passing vessels, making them significantly harder to detect than moored varieties – and more dangerous than contact mines because the ship doesn’t even need to touch the mine to trigger an explosion.
- ‘Smart’ and rocket mines: More advanced systems, including reportedly imported Chinese EM-52 rocket mines, remain moored on the seabed at depths of up to 200 metres (656ft). When they detect a ship sailing overhead, they release a rocket that strikes the vessel’s underside.
Where are sea mines placed in the strait?
There is no clear answer. The Iranians have not officially disclosed whether or where they have placed mines, stating only that there may be mines in the strait. The fact that US warships are currently searching for mines suggests Washington does not know the location of possible mines either.
If deployed, however, military analysts at the Washington Institute for Near East Policy noted that the placement of these mines is likely to have been strategically calculated to exploit the geography of the Gulf, forcing international traffic into narrow, vulnerable channels.
As the map released by the IRGC last week showed, Iran is clearly directing shipping traffic to travel much closer to its coast than it had done before.
Speaking to Al Jazeera, Alexandru Cristian Hudisteanu, a retired Romanian naval officer and MARSEC (the North American three-tiered maritime security system) professional, explained that in wargaming scenarios, systematic mining is used to deny access to specific water spaces. “For a strait, one example would be to mine the whole width of the passageway or to deny a section of the actual strait,” Hudisteanu explained.
But he warned that the physical location of mines matters less than the psychological effect they induce. “The mined area does not have to be everywhere to be everywhere in the minds of those who must transit it,” he said.
Can the US counter Iranian mine-laying operations?
The political tensions surrounding the Strait of Hormuz have reached a fever pitch. In early March, a senior IRGC adviser declared the strait “closed” to enemies while permitting select vessels to pass.
US President Donald Trump has asserted that US forces have destroyed “all” 28 Iranian mine-laying boats. Trump warned of consequences “at a level never before seen” if the mines are not removed.
While CENTCOM has confirmed striking 16 Iranian vessels in an initial wave of attacks, the destruction of an entire mine-laying fleet remains unverified by independent sources.
How easy is it to clear sea mines?
The process of clearing mines – known as mine countermeasures (MCM) – is slow, methodical and high risk. It involves “mine hunting”, using high-resolution sonar to find individual mines, and “minesweeping”, using mechanical or magnetic systems to trigger them.
However, the US Navy is facing what experts call a “mine gap”. The FPRI’s analysis detailed how institutional neglect had led to the retirement of dedicated MCM assets just months before this war. The Navy decommissioned its last four Avenger-class MCM ships in Bahrain in September. Additionally, the MH-53E Sea Dragon helicopters, long the backbone of airborne minesweeping, were phased out in August, it reported.
The current US strategy relies on small combat ships built for coastal operations and fitted with MCM mission modules. However, only one of these vessels, the USS Canberra, is currently available in the region.
“MCM units tend to be good at one single job and lousy at anything but minimal point defence,” Hudisteanu told Al Jazeera. He explained that while conducting clearance, these vessels are “virtually sitting ducks” for coastal missiles or fast attack craft, requiring a massive protective screen of destroyers and aircraft to operate.
