Forty-seven years of revolution, tanker wars, seizures, and threats to close the world's most consequential oil passage.
The Strait of Hormuz has been the world’s most dangerous oil passage for nearly half a century. Each entry below is a dated, verifiable event; together they show a pattern — threats to close the strait are frequent, actual closure has never happened, and harassment short of closure has repeatedly repriced the world’s oil.
1979 — The Iranian Revolution topples the Shah and establishes the Islamic Republic; US–Iran relations break down, and the Gulf becomes a front line.
1979–1981 — Iranian students hold 52 Americans hostage at the US embassy in Tehran for 444 days; the crisis deepens Gulf tensions.
1980 — Iraq invades Iran, beginning the eight-year Iran–Iraq War; Gulf shipping becomes a target for both sides.
1984–1988 — The “Tanker War”: Iran and Iraq attack Gulf shipping. In 1987 the United States reflags Kuwaiti tankers and escorts them (Operation Earnest Will).
1988 — The USS Vincennes shoots down Iran Air Flight 655 over the strait, killing all 290 people aboard; the United States later pays compensation.
1988 — Iran and Iraq accept a ceasefire; attacks on Gulf shipping end.
1990–1991 — Iraq invades Kuwait; a US-led coalition drives it out. The strait stays open through the Gulf War.
2003 — The US-led invasion of Iraq brings another war to the Gulf; coalition navies protect shipping through the strait.
2007–2008 — Iranian speedboats confront US warships in the strait, including a widely reported January 2008 incident; the encounters raise fears of miscalculation.
2011–2012 — Iran threatens to close the strait as sanctions tighten over its nuclear programme; the European Union embargoes Iranian oil in January 2012. The threat is not carried out.
2015 — The JCPOA nuclear deal is agreed in July; sanctions relief follows in January 2016.
2016 — Iran detains ten US sailors whose boats stray into Iranian waters; they are released the next day.
2018 — The United States withdraws from the JCPOA in May and reimposes sanctions on Iran.
2019 — Tankers are attacked off Fujairah and in the Gulf of Oman in May and June; the United States blames Iran, which denies responsibility.
2019 — Iran seizes the British-flagged tanker Stena Impero in July; it is released in September.
2020 — The United States kills Iranian general Qassem Soleimani in January; Iran vows retaliation and the Gulf goes on alert.
2021 — Iran and world powers resume talks in Vienna on restoring the nuclear deal; the talks stall without agreement.
2023 — The United States seizes an Iranian oil cargo; Iran seizes tankers in the Gulf, including the Advantage Sweet and the Niovi.
2024 — Iran seizes the MSC Aries near the strait in April, amid a sharp Israel–Iran escalation.
2026 — Israel and Iran are at war; the Bureau’s World Barometer rates the Strait of Hormuz Critical, describing harassment of shipping rather than a full closure.
Sources
U.S. Energy Information Administration, World Oil Transit Chokepoints (2025) — baseline flows through the strait.
