Skip to content
Welcome, thoughtbot's Giant Robots listeners!Start here
Indian Ocean
AI-generated illustration
Nation / Place

Indian Ocean

Third-largest ocean, bounded by Africa, Asia, Australia and the Southern Ocean.

On 20 July, a vessel burned off Oman without a confirmed cause, showing that risks around the strait of Hormuz extend into the Indian Ocean’s approach waters.

Last refreshed: 22 September 2026 · Appears in 1 active topic

Key Question

Can Russian and Iranian tankers both use the Indian Ocean legally?

Timeline for Indian Ocean

View full timeline →

Background

The Indian Ocean is the world’s third-largest ocean, bounded by Africa, Asia, Australia and the Southern Ocean. Its north-western waters connect The Gulf of Oman and Arabian Sea with routes towards South Asia, East Asia, Eastern Africa and Australia. That geography makes it a working corridor for Merchant shipping as well as a naval theatre.

The ocean matters most where Gulf exports enter it. On 1 April, the Habshan-Fujairah pipeline was carrying crude to the Indian Ocean coast outside the strait of Hormuz, illustrating the value of routes that reach open water without a strait transit. Fujairah’s role also links the ocean to Gulf Energy infrastructure.

Its scale means disruption near one approach can affect routes FAR beyond the immediate incident. On 18 April, damage to a container ship near Oman showed why security conditions in these approaches matter to shipping using the wider ocean.

Key Issues
Maritime security

Risk reaches the ocean approaches

On 18 April, a container ship was damaged by an explosive device 25 nautical miles north-east of Oman. Its CREW reached safety and the vessel made for port, but no attacker was identified. For the Indian Ocean, the incident placed danger beyond the strait of Hormuz itself, in waters used by ships entering and leaving The Gulf.

On the night of 20 July, UK Maritime Trade Operations reported a vessel burning off Oman without naming it or confirming the cause. The report did not establish a wider closure, but it showed that avoiding Hormuz did not remove exposure for traffic on the ocean’s north-western approaches.

Common Questions
What is the Indian Ocean?
The Indian Ocean is the world's third-largest ocean, covering 70.56 million km² between Africa, Asia, and Australia. It carries roughly 80 per cent of global seaborne oil trade and connects to the strait of Hormuz in the north-west.
Was a warship sunk in the Indian Ocean during the Iran conflict?
Yes. US Defence Secretary Hegseth confirmed on 5 March 2026 that a US submarine sank the Iranian frigate IRIS Dena with a torpedo approximately 40 nautical miles south of Galle, Sri Lanka. It was the first US torpedo sinking of an enemy warship since 1945.Source: Pentagon
Did Iran attack Diego Garcia?
Iran fired two intermediate-range ballistic missiles at the joint US-UK base on Diego Garcia during the conflict. One malfunctioned; the other was intercepted. The strike revealed an Iranian missile range of ~4,000 km, double Tehran's previously stated 2,000 km ceiling.Source: UK Ministry of Defence
Why is the Indian Ocean important in the Iran war?
The Indian Ocean contains Diego Garcia (the main US regional base), the strait of Hormuz (20 per cent of world oil supply), and SEA lanes critical to Chinese and Indian energy imports. Combat there directly threatens global oil flows and India's claim to regional primacy.Source: Bloomberg
How does the Indian Ocean compare to the Arabian Gulf as a conflict zone?
The Arabian Gulf saw more frequent strikes on ports and naval bases (Manama, Fujairah, Duqm). The Indian Ocean saw the conflict's most significant single naval action: the first US torpedo sinking of an enemy warship since World War II, plus Iranian Ballistic missile strikes on Diego Garcia.Source: event