The week of September 28 to October 5 was the worst for tankers in the Strait of Hormuz since the war began on February 28. Tracking sources counted at least 12 attacks on oil, LPG and LNG carriers in those seven days. The IMO, which is slower to verify, had confirmed nine. The previous worst week, in mid-July, had eight.

Where the ships were hit matters more than how many. Almost every strike in that stretch landed in the southern channel, a few miles off Oman’s coast. That is the lane shipowners moved to in June, when Muscat’s corridor offered a way past Iran’s tolled northern route. It was supposed to be the workaround. Iran is now treating it as a firing range.

Six months into the war, nobody can agree on how many ships are getting through the Strait of Hormuz. Washington says traffic is climbing and the lanes are clear. Tehran says the strait is shut to anyone it hasn’t approved. The commercial trackers, the ones insurers and oil desks pay for, land a lot closer to Tehran’s picture.

The gap is wide. On 1 September two US officials said 40 commercial ships had crossed under naval escort carrying roughly 18 million barrels of oil, a wartime record. Kpler counted 11 vessels that day.

President Trump asked his followers on Wednesday whether the Strait of Hormuz should be renamed the Trump Strait. The reason he gave was ownership. “Now that we have it under U.S.A. control,” the post began, before promising the new name would be hotter than ever before, like America itself. Thank you for your attention to this matter.

The timing is the interesting part. He posted this the day after telling the same audience that the American position in the war is fine because Washington has almost total control of the strait. Almost. Three weeks earlier there was no qualifier at all, just total control and a naval blockade being called a wall of steel. The trophy is being engraved while the claim behind it is quietly shrinking.

The palaces on this stretch of water were paid for by a rent extracted from geography. Venice sat where the Levant trade entered Europe, taxed what passed, and converted the proceeds into a navy that protected the arrangement. For roughly four centuries this worked better than almost any other business model available to a European state. Then it stopped working, and the reasons it stopped are directly relevant to every state whose strategic position rests on a strait.

A shipping lane that hugs the Omani coastline is doing something the IRGC cannot tolerate: it lets tankers leave the Persian Gulf without asking Tehran for permission. Oman, working with the International Maritime Organization, has now formalized a temporary, fee-free corridor through the southern half of the Strait of Hormuz, with explicit navigational coordinates issued jointly by Muscat and the IMO. Muscat frames it as freedom-of-navigation housekeeping. For Iran, it is a structural threat to the one piece of leverage the war left it holding.

The ceasefire was already fragile. The Iranian delegation had barely landed in Doha. And then the Islamic Revolutionary Guard Corps Navy fired on a US oil tanker attempting to transit the Strait of Hormuz.

That is the situation as of the early hours of May 28. According to IRGC-affiliated Tasnim News, an American oil tanker entered the strait with its radar system switched off — a provocation, in Tehran’s framing — and was turned back after IRGC naval forces fired toward the vessel. The US struck what it described as a “burnt area” near Bandar Abbas in response. No casualties were reported on either side.

A bulk carrier was struck by an unknown projectile on Sunday morning approximately 23 nautical miles northeast of Doha, igniting a fire aboard the vessel, the United Kingdom Maritime Trade Operations Centre confirmed. The fire was subsequently extinguished. No casualties or environmental damage were reported.

The attack is the latest in a sustained campaign of maritime strikes across the Persian Gulf following the shaky ceasefire that halted direct US-Iran combat operations. No party has formally claimed responsibility, but the strike follows explicit warnings issued hours earlier by Brigadier General Amir Akraminia, spokesman for the Iranian Army, who stated that countries enforcing sanctions against Iran “will certainly face problems passing through the Strait of Hormuz.”

U.S. Central Command released footage on May 8 documenting the interdiction of two Iranian-flagged tankers, the Sea Star III and the Sevda, as they attempted to breach the U.S. naval blockade and enter an Iranian port. A Navy F/A-18 Super Hornet operating from the USS George H.W. Bush struck both vessels’ smokestacks with precision munitions, disabling them before they could reach their destination. CENTCOM confirmed neither tanker continued its transit toward Iran.

The Strait of Hormuz has been effectively closed since the war began on February 28. Iran sealed it — intermittently at first, then completely — as its primary lever of economic coercion, blocking a waterway through which roughly 20 percent of the world’s crude oil normally passes. The result: stranded vessels, approximately 20,000 seafarers trapped aboard ships with nowhere to go, and gasoline prices in the United States approaching $4.44 per gallon, up nearly 50 percent since the conflict began.

The 2019 attack on the Abqaiq oil processing facility used cruise missiles and drones. The subsequent attacks on tankers in the Gulf of Oman used limpet mines and, in some cases, explosive-laden fast boats. By the time Houthi forces began their Red Sea campaign in late 2023, the weapons mix had evolved to include one-way attack drones and ballistic missiles fired against commercial vessels. The technological trajectory is consistent: unmanned systems are becoming a larger share of the threat to shipping in and around the Persian Gulf, and their characteristics — low cost, deniability, saturation potential, and steadily improving accuracy — make them a structural shift rather than a tactical adaptation.

The Strait of Hormuz has a sister chokepoint at the other end of the Arabian Peninsula. Bab-el-Mandeb, the narrow passage between Yemen and Djibouti that connects the Red Sea to the Gulf of Aden, carries the maritime traffic of the Suez Canal route — container ships, bulk carriers, tankers moving between Europe and Asia, and LNG vessels serving European regasification terminals. When Houthi forces in Yemen began attacking commercial shipping in the Red Sea in late 2023, they demonstrated that Iran’s sphere of proxy influence could threaten two of the world’s most critical maritime corridors simultaneously.

Fujairah sits on the Gulf of Oman coast of the United Arab Emirates, on the far side of the Hajar Mountains from Dubai and Abu Dhabi. For most of its history it was the smallest and least developed of the seven emirates, with a fishing economy and a geography that made connection to the Emirati interior difficult. What transformed Fujairah was the recognition, by Abu Dhabi planners and international oil traders simultaneously, that a port on the Gulf of Oman side of the UAE was worth more than a port on the Arabian Gulf side because it lay outside the Strait of Hormuz. Its strategic value is a function of what it avoids.

The Strait of Hormuz has never been closed. The threat of closure has been used repeatedly as a diplomatic instrument by Iran, and incidents in the strait have periodically elevated insurance premiums, rerouted tankers, and spiked oil prices. What has not happened, in the modern era of global oil dependence, is a complete cessation of transit. This absence of precedent does not mean the scenario is implausible. It means that the consequences of closure must be modeled rather than observed, and the models are sobering.

Between 1984 and 1988, Iranian and Iraqi forces attacked approximately 500 commercial vessels in the Persian Gulf. The Tanker Wars — that portion of the Iran-Iraq conflict that spilled into the maritime domain — were the most sustained campaign of attacks on commercial shipping since the Second World War. They established the template for how straits and sea lanes become instruments of war, how insurance markets respond to sustained maritime threats, and how major powers calculate the costs and limits of intervention in Gulf conflicts. The lessons were not adequately remembered in subsequent decades.

Approximately 20 million barrels of oil and petroleum products transit the Strait of Hormuz on an average day. The figure is so large and repeated so frequently in energy commentary that it has become almost abstract. Decomposing it into its constituent flows reveals a more specific picture of what is actually at stake — which countries, which companies, which commodity streams, and which supply chains run through twenty-one miles of contested water.

The Strait of Hormuz is a strait used for international navigation overlapping with the territorial waters of Iran and Oman. Under the United Nations Convention on the Law of the Sea, such straits are subject to the right of transit passage — a legal regime that grants all ships and aircraft the right to continuous and expeditious transit, and that limits the ability of coastal states to interfere with that transit. Iran has not ratified UNCLOS. It does not accept the transit passage framework. This legal disagreement is not merely academic. It is the normative foundation on which Iran’s claimed right to close or restrict the strait rests, and the normative foundation that every other party invokes to deny Iran that right.

The Strait of Hormuz is 90 miles long and between 21 and 55 miles wide. The navigable channel — the portion deep enough for laden very large crude carriers and the other substantial vessels that transit it — is much narrower. Two traffic separation lanes, each approximately two miles wide, handle the inbound and outbound commercial traffic, separated by a two-mile buffer zone. The effective transit corridor for a laden supertanker is therefore something on the order of two miles across, within a strait that appears much wider on maps but that shallow water, islands, and navigational hazards reduce to a constrained passage at the critical point.

Before a single missile is fired, before a mine is laid, before a naval vessel changes course, the insurance market registers the threat. War risk premiums on tankers transiting the Persian Gulf are among the most sensitive geopolitical indicators available. They move faster than official statements, faster than military repositioning, and faster than most news coverage. The underwriters at Lloyd’s of London are not strategists, but their pricing reflects a continuous aggregation of threat intelligence that rivals most government assessments.