The Strait of Hormuz and the Geography of Energy Security

Geography rarely makes headlines, but it quietly structures the choices of states. Nowhere is this clearer than at the Strait of Hormuz, the passage between Iran and the Musandam Peninsula of Oman that connects the Persian Gulf to the Gulf of Oman and the open ocean.

At its narrowest the strait is about 21 miles wide. The shipping lanes themselves are far narrower: two channels, each two miles wide, separated by a two-mile buffer. Through them passes roughly a fifth of global oil consumption and a comparable share of the world’s trade in liquefied natural gas, much of it from Qatar.¹

A chokepoint without a real bypass#

The significance of Hormuz lies less in the volume of traffic than in the absence of alternatives. Other chokepoints can be circumvented, at a cost. The Suez Canal can be avoided by sailing around the Cape of Good Hope; the Bab el-Mandeb by the same long route. For most Gulf producers, there is no equivalent detour.

Two pipelines offer partial relief. Saudi Arabia’s East–West pipeline carries crude from the Eastern Province across the peninsula to Yanbu on the Red Sea, and the United Arab Emirates’ Habshan–Fujairah line delivers oil to a terminal on the Gulf of Oman, beyond the strait. Together they can divert only a fraction of normal flows. Iraq, Kuwait and Qatar have no comparable outlet at all.

Why the threat is made — and rarely carried out#

Iranian officials have periodically threatened to close the strait, usually in response to sanctions or military pressure. The threat is credible in one sense: Iran’s long coastline, its islands near the shipping lanes, and its arsenal of mines, fast attack craft and anti-ship missiles give it real capacity to disrupt traffic.²

But the threat has been made far more often than it has been acted upon, for several reasons:

• Iran needs the strait too. Its own oil exports and a large share of its imports pass through the same waters.
• Closure invites overwhelming response. A sustained closure would likely unite the Gulf states, Western navies and major Asian importers against Tehran.
• Disruption is more useful than closure. The ability to raise insurance premiums, harass tankers and create uncertainty offers leverage at a much lower cost than a full blockade.

The lesson of the Tanker War#

The closest precedent is the so-called Tanker War of 1984–88, during the Iran–Iraq War, when both sides attacked shipping in the Gulf. Hundreds of vessels were struck, yet traffic never stopped. In 1987 the United States began escorting reflagged Kuwaiti tankers in Operation Earnest Will, and in April 1988, after a US frigate struck an Iranian mine, it launched retaliatory strikes on Iranian platforms and naval vessels. The episode showed both how vulnerable shipping was and how difficult it was to halt it altogether.

The strategic value of Hormuz lies not in the ability to close it, but in the ability to make everyone wonder whether it might be closed.

Law, sovereignty and the lanes#

The legal position adds a further layer. The inbound and outbound lanes lie within Omani territorial waters, while Iran controls several islands near them — including Abu Musa and the Greater and Lesser Tunbs, whose sovereignty the UAE disputes. The 1982 UN Convention on the Law of the Sea grants ships a right of transit passage through straits used for international navigation. Iran has signed but not ratified the convention and interprets the rules more restrictively; the United States, which has not joined the convention either, treats transit passage as customary international law. These differences are usually academic, but they matter in a crisis.

What to watch#

Energy security in the Gulf depends on the interaction of geography, military capability and the calculations of exporters and importers alike. The key indicators for analysts are therefore not only military:

1. Bypass capacity — any expansion of pipelines to the Red Sea or the Gulf of Oman.
2. War-risk insurance premiums — often the fastest signal of perceived danger.
3. Asian demand — as China, India, Japan and South Korea take most Gulf exports, their diplomacy increasingly shapes the strait’s politics.
4. Naval presence — who patrols, who escorts, and who is invited to do so.

Hormuz will remain a place where local rivalries and global markets meet in a very small space. Its narrowness is its power.