The Strait of Hormuz is a geographic choke point where global energy security rests on a razor's edge. At its narrowest, the waterway spans just 21 miles, forcing roughly 20 million barrels of oil, nearly a fifth of global daily consumption, through shipping lanes only two miles wide. It is the world's most vital artery, and as of this weekend, it has been severed.
(Photo by Bedirhan Demirel/Anadolu via Getty Images)
Following the launch of Operation Epic Fury on February 28, tankers have been forced to drop anchor in the Gulf of Oman, paralyzing nearly 20% of the world's petroleum supply. Operation Epic Fury — a massive, high-stakes gamble by U.S. and Israeli forces — ripped through a target list spanning from the industrial hubs of Isfahan to the core of Tehran. The strikes targeted the compound where Supreme Leader Ayatollah Ali Khamenei was killed. By early Saturday, the IRGC had hijacked maritime radio frequencies, broadcasting threats that turned the shipping lanes into a dead zone.
Though Iran's Foreign Minister later stated there was no plan to close the Strait completely, shipping data showed maritime traffic largely paused, and an oil tanker was attacked off Oman's coast Sunday.
The threat calculation has grown more urgent as U.S. intelligence assessments indicate Tehran maintains between 5,000 and 6,000 naval mines, with the capability to seed the Strait at rates up to 100 mines per day through its fleet of submarines. A handful of deployed mines would paralyze the Strait. Global insurers will pull coverage the moment ordnance is confirmed, forcing tankers to drop anchor or turn back. For Gulf producers, storage tanks will reach capacity within days, likely forcing a total cap on well production by the end of the week.
"The IRGC has naval bases to the North and South of the Strait of Hormuz that could deploy sea mines in a matter of hours," Iranian military analyst John Wood tells The Cipher Brief.
But whether Iran's sea mine arsenal proves to be a potent threat to United States forces and global interests in Hormuz is yet to be seen.
During the 1988 Tanker War, Iran deployed approximately 150 mines in the Strait of Hormuz. One of which nearly sank the USS Samuel B. Roberts, a guided-missile frigate. The mine that struck the Roberts was World War I vintage, demonstrating that naval mines need not be sophisticated to prove effective. Since 1950, mines have inflicted 77 percent of U.S. ship casualties, a higher damage rate than any other weapon system.
The challenge for Tehran, however, lies not in the mines themselves but in deployment. Iran operates only three Kilo-class submarines capable of laying the more complex EM-52 rising mines, and its fleet of approximately 20 Ghadir-class midget submarines. Each carries just four mines via torpedo tubes and has a relatively short range when operating in stealth mode.
Iranian commanders aren't necessarily looking for a traditional naval standoff in the Strait. Instead, they've rigged an economic tripwire. The goal isn't to sink the U.S. Fifth Fleet but to make the price of any confrontation too high for the global market to stomach.
A mine-clearing operation would require at least a month to establish a safe corridor, during which Gulf oil production would halt, storage facilities would fill, and producers would be forced to cap wells.
The Global Energy Chokepoint
Approximately 21 percent of global petroleum liquids pass through the Strait of Hormuz, making it the world's most critical oil transit chokepoint. Saudi Arabia, the UAE, Kuwait, and Iraq depend on the Strait for virtually all their seaborne crude exports.
"There are over 150 tankers bottled up to the North of the Strait of Hormuz," Wood explains, referring to tankers unable to transit. "Insurance companies are canceling policies altogether. If you sink a fully loaded VLCC, that could be up to an approximate $40 million loss."
A Very Large Crude Carrier can transport up to 2 million barrels of oil, enough to supply a medium-sized refinery for weeks. At current market prices, a single loaded vessel represents a cargo value exceeding $140 million, making the insurance exposure catastrophic if even a handful of ships are damaged or sunk.
If the IRGC manages to seed the lanes, the resulting supply shock won't be measured in days but in weeks. The Navy maintains a limited fleet of dedicated mine countermeasure vessels, a force structure analysts consider insufficient for the scale of potential mining operations in waters where Iran could sustain deployment campaigns for up to six months using its mine stocks and submarine fleet. Tehran's strategic advantage lies in asymmetry: deploying mines requires minimal resources at rates of up to 100 per day, while clearing them demands painstaking work under fire from coastal anti-ship missiles, swarm boats, and drone strikes.
Norm Roule, who served as the National Intelligence Manager for Iran at the Office of the Director of National Intelligence and spent 34 years with the Central Intelligence Agency, tells The Cipher Brief that, despite concerns, contingencies have been in place for decades.
"Do you think Donald Trump is going to sit back and let the Iranians mine the Persian Gulf? I don't," Roule says. "If anybody splashes something in the water, we'll open all the gates of hell on them."
Any Iranian attempt to physically deploy mines would likely trigger immediate U.S. military retaliation against Tehran's naval assets and coastal infrastructure before a minefield could be established.
Roule emphasizes the intelligence dimension: distinguishing between defensive mine deployments in Iranian territorial waters and offensive operations targeting international shipping lanes becomes critical, as striking mines within Iran's waters could constitute an act of war regardless of their intended purpose.
"You need intelligence on what they're dropping," he says. "If they deploy something in their own waters, are they defensive or offensive mines? If you attack them in their waters, you're starting a war."
Current Military Posture
Yet the window for Iranian mine deployment may already be closing as U.S. forces maintain round-the-clock surveillance and strike capabilities positioned to interdict any large-scale mining attempt. Roule dismisses concerns about American response capabilities, noting American naval forces maintain a substantial forward presence with two carrier strike groups supported by more than 150 aircraft and dozens of warships.
"They're already there," he insists. "Aircraft can take off from the USS Abraham Lincoln and be over targets within minutes. Our geospatial assets are almost certainly monitoring for unusual Iranian activity."
That surveillance appears to have already shaped operational targeting: the initial wave of U.S.-Israeli strikes targeted not only nuclear and leadership sites but also Iranian naval infrastructure, with President Trump stating the operation aimed to "destroy the country's navy." This suggests Washington sought to neutralize mine-laying capabilities before they could be deployed.
Should Iran deploy mines despite U.S. interdiction efforts, the Navy would need to send minesweepers through the narrow shipping lanes, demonstrating safe passage to reassure commercial traffic and insurers.
Iranian Calculations
Yet Tehran faces its own constraints in executing a Strait closure, as halting energy flows would inflict economic damage on Iran itself and key trading partners whose support the regime cannot afford to lose.
The oil market's immediate response has reflected both fear and hedging: at least 150 tankers have dropped anchor in open Gulf waters beyond the Strait of Hormuz rather than risk transit. Despite the disruption, oil prices remain below $100 per barrel, and neither the United States nor major Asian consumers have tapped strategic petroleum reserves.
Gulf producers had anticipated potential disruptions: Saudi Arabia maximized throughput on its East-West pipeline to Red Sea ports, while the UAE pushed additional volumes through its Fujairah terminal on the Gulf of Oman, bypassing the Strait entirely.
"Short term, oil could jump $10–$15 as markets react," Roule projects. "But unless tankers are sunk, or there are major hits on infrastructure like Kharg Island or Abqaiq, this is likely temporary. Oil might remain in the high $60s or low $70s, with a short-term bump."
Tehran's strategic logic centers on economic leverage rather than military victory: forcing a disruption severe enough that global pressure on Washington to de-escalate outweighs the costs Iran absorbs from halted oil exports. The gambit depends on speed, inflicting maximum economic pain before the U.S. can establish alternative supply routes or before domestic Iranian shortages undermine regime stability.
"If I'm Iran and I shut it down, I'm doing it to hurt the U.S. and the global economy so that the world pressures Washington to ease up," Roule asserts.
The tankers currently anchored in Gulf waters face a bureaucratic obstacle: insurance underwriters have either pulled coverage entirely or raised premiums by 50-60 percent, while administrative processing could mean vessels remain idle for a week or more, even if military tensions ease.
"I'm not sure Iran has the time to create the strategic impact it wants," Roule surmises. "What people overlook is the tremendous amount of food and commodities that keep the region's economies going. If the Iranians shut the Strait of Hormuz, they're choking not only their oil economy but also their broader economy: iron, basic materials, things they need to keep industries running."
China's role complicates Tehran's calculus. In 2025, China bought over 80% of Iran's crude exports, with a quarter of its entire national energy supply currently funneling through the Strait. A deep freeze on transit forces a brutal trade-off: Beijing must either double down on its Tehran partnership or pivot to save the manufacturing engines that prevent a domestic crash.
This creates a high-stakes "economic veto." Chinese refineries and factories can't weather a long-term shutdown, and Tehran's economy — stripped of other buyers by sanctions — has no pulse without Chinese cash. This shared vulnerability tethers Iran. They can only push the West so far before they sever the very lifeline keeping the regime solvent.
The Escalation Threshold
Washington's willingness to strike preemptively rather than wait for mines to be deployed marks a fundamental shift in decades of deterrence doctrine. Roule places current tensions within a broader historical framework: multiple U.S. administrations prepared military options against Iran, yet consistently chose restraint. Trump represents the first president willing to execute those strikes.
U.S. intelligence detected Iranian forces loading naval mines during the June 2025 conflict, though the mines were never deployed. This suggests Washington's surveillance capabilities and demonstrated willingness to strike preemptively may deter Tehran from attempting large-scale mining operations.
The compressed geography of the Strait, shipping lanes just two miles wide flanked by Iranian coastal batteries and missile sites, means response times are measured in minutes, placing a premium on the extensive training U.S. naval forces have conducted for this scenario.
"It's a small area," Roule adds. "When something is fired, there's not a lot of time. Our Navy has practiced this extensively. There's a lot of experience there."
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