Overview
The Strait of Hormuz is a narrow waterway between Iran to the north and the United Arab Emirates and Oman to the south, connecting the Persian Gulf to the Gulf of Oman and the Arabian Sea. At its narrowest, the strait is approximately 33 kilometers (21 miles) wide, with two navigable shipping lanes each 3.2 kilometers wide. It is the world's single most important oil chokepoint.
Strategic Importance
Approximately 20–21% of the world's total petroleum liquids consumption — roughly 17–18 million barrels per day — transits the Strait of Hormuz. This includes crude oil from Saudi Arabia, Iraq, Iran, Kuwait, the UAE, and Qatar, as well as liquefied natural gas (LNG) from Qatar, which is the world's largest LNG exporter. There is no viable pipeline alternative capable of replacing this volume. Closure of the strait, even temporarily, would cause an immediate global energy crisis.
Key Facts
17–18 million barrels of oil per day transit — approximately 20% of global supply
Narrowest navigable width: ~3.2 km per lane (inbound and outbound)
Iran controls the northern shore; UAE and Oman the southern shore
The US Navy's Fifth Fleet is based in Manama, Bahrain, specifically to protect free transit
Iran has repeatedly threatened to close the strait during periods of US-Iran tension
The IRGCN (Islamic Revolutionary Guard Corps Navy) operates fast-attack craft and submarines in the strait
Approximately 50–80 tankers transit daily under normal conditions
Current Risk Assessment
Iran's nuclear programme and ongoing US sanctions create persistent escalation risk. The IRGCN has a documented pattern of harassing, boarding, and seizing commercial vessels — particularly tankers with links to Israel, the UK, or US-sanctioned entities. The risk of strait closure is considered extreme-tail but non-zero. War-risk insurance premiums for Persian Gulf and Hormuz transits reflect this persistent background threat.
Historical Context
During the 1980–1988 Iran-Iraq War, the Strait of Hormuz was the site of the 'Tanker War,' in which hundreds of commercial vessels were attacked by both sides. The US Navy conducted Operation Earnest Will (1987–88) to escort Kuwaiti tankers through the strait. In 2019, Iran-linked forces conducted limpet mine attacks on tankers off Fujairah and in the Gulf of Oman, and the IRGCN seized the British-flagged Stena Impero. In 2023–2024, the IRGCN escalated seizures of vessels linked to Israel and Western interests, including the MSC Aries in April 2024.