Iran Didn't Close the Strait of Hormuz — Cheap Drones Did: The Most Important Shipping Lane on Earth Is Empty

The most remarkable fact about the closure of the Strait of Hormuz — the waterway through which approximately 20% of the world's daily oil supply flows — is not that it happened. It is how it happened. Iran did not lay mines across the two-mile shipping lanes. It did not deploy its surface fleet to physically block passage. It did not even need to fire missiles at every vessel attempting to transit. All Iran had to do was launch several drone strikes in the vicinity of the strait — and the global insurance market did the rest. Ship traffic through the Strait of Hormuz has now collapsed from an average of 153 vessel transits per day in the weeks before the conflict began to a daily average of just 13 since March 1 — a reduction of approximately 90%. On the worst days, the number of ships broadcasting automatic identification system signals while transiting the strait has dropped to effectively zero. The world's most important maritime chokepoint has emptied itself — not because Iran physically closed it, but because no insurance company on earth will underwrite the risk of a ship attempting to pass through it. How an Insurance Decision Closed the World's Most Critical Waterway The mechanism by which the Strait of Hormuz closed is one of the most important — and least discussed — stories of the entire conflict. War risk insurance for vessels operating in the region was effectively withdrawn at midnight on March 5. Without war risk cover, shipowners face catastrophic uninsured financial exposure if their vessel is struck, damaged, or sunk in the strait. The value of a modern VLCC supertanker — the class of vessel that carries the bulk of Gulf oil exports — is approximately $100-130 million. No rational commercial shipowner will risk losing a $100 million asset without insurance. And no insurance company will currently write a policy for transit through a waterway where the Joint Maritime Information Centre has upgraded its risk assessment to Critical — its highest level, indicating that an attack is almost certain. The result is a closure that is not legally formal but is operationally absolute. As the world's foremost maritime legal experts put it plainly: is the Strait of Hormuz legally closed? No. Is it effectively closed to almost all international commercial shipping? Yes. 153 Ships Per Day to Near Zero: The Data The scale of the collapse in Strait of Hormuz traffic is almost impossible to overstate. In the weeks before Operation Epic Fury began on February 28, the strait was averaging more than 153 vessel transits per day — with oil tankers and container ships together making up approximately 88% of that traffic. On February 28 itself — the day of the opening US and Israeli strikes — 105 ships transited the strait, approximately 68% of typical volume. Since March 1, only 78 vessels in total have been detected passing through the strait over ten days — a daily average of just 13. That figure includes vessels of all types, including those turning around after partial transit. The number of crude oil tanker transits has fallen to near zero. No LNG carrier transits have been recorded since the conflict began. The approximately 500 million barrels of oil that typically flow through the strait every month — one fifth of the world's supply — has effectively stopped moving. As digital8hub.com has reported, oil prices have surged from approximately $70 per barrel before the conflict to $119 at their peak, with WTI currently trading above $100 for the first time since 2022. China's Ships Are Trapped Too One of the most significant revelations of the past week has been the collapse of early reports suggesting China had negotiated privileged passage for its vessels through the strait. Those reports were false — or at best, wildly premature. Between February 23 and 28, AIS data shows that more than 49 Chinese and Hong Kong-flagged vessels transited the Strait of Hormuz normally. Since March 1, just two Chinese-flagged ships have been observed transiting — one that managed to pass in daylight on March 1, and one that turned off its AIS transponder and made a midnight run before reappearing in the Gulf of Oman hours later. As digital8hub.com has reported, China has publicly urged all parties to keep the strait open to international trade — but Beijing's leverage over Iran's military operations is considerably more limited than its diplomatic posture suggests. The practical result is that 55 Chinese-flagged ships are now trapped inside the Persian Gulf, unable to exit. An unknown number of additional Chinese vessels are idling outside in the Gulf of Oman, unable to enter. China imports as much as 40% of its oil and 30% of its LNG through the strait. The closure is not merely a Western problem. The Reroute: Cape of Good Hope, Two Extra Weeks, Higher Costs For vessels that cannot or will not wait for the situation to resolve, the alternative is a reroute around Africa's Cape of Good Hope — the same diversion that redirected global shipping when Yemen's Houthi rebels made the Red Sea too dangerous in 2024. The Cape of Good Hope reroute adds approximately two weeks to transit times between the Middle East and Europe or Asia, significantly increases fuel consumption and costs, and removes significant cargo capacity from global trade because the same vessels are spending more time at sea on each voyage. The cost implications are already flowing through to global freight rates. The environmental implications — longer distances, higher speeds to meet delivery commitments, increased carbon intensity — are a secondary but real consequence. For now, vessels are anchoring and waiting — as digital8hub.com has reported, approximately 3,200 commercial vessels remain idle in the Gulf, with 150+ tankers anchored outside the strait. Trump has claimed the war is "pretty much complete" — but the ships that need to move their cargo are not yet moving. For the latest updates on the Hormuz crisis and global energy markets, follow digital8hub.com.