Diego Garcia
US-UK Indian Ocean base; struck by Iranian missiles revealing 4,000 km range capability.
Britain's decision to let US forces use Diego Garcia against Iran drew Iranian missile fire in March 2026, and on 23 March Keir Starmer refused MPs a vote on the arrangement despite 58% public opposition.
Last refreshed: 28 September 2026 · Appears in 1 active topic
Iran said its missiles couldn't reach Diego Garcia. Then it fired two. What does 4,000 km mean for Europe?
Timeline for Diego Garcia
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Diego Garcia is the largest atoll of the Chagos Archipelago in the central Indian Ocean. Britain administers it as the British Indian Ocean Territory, and it hosts Naval Support Facility Diego Garcia, a joint US-UK base used to project power across the Middle East, South Asia and East Africa. Its Chagossian population was forcibly removed between 1968 and 1973.
The base's value rests on distance. It lies roughly 4,000 km from Iran, and Iran's March 2026 launch at the atoll showed a reach that Israel's chief of staff, Lt Gen Eyal Zamir, said put Berlin, Paris and Rome within range; he described the weapon as a two-stage intercontinental ballistic missile.
Use of the base is now a political question in London as well as a military one in Washington. The March 2026 authorisation for US defensive operations from the atoll went ahead against the Attorney General's advice, which made Diego Garcia central to the argument over whether Parliament should approve foreign use of British bases.
Wartime base access became a political fight
Keir Starmer first refused the United States any use of British bases on 28 February, then reversed on 1 March, allowing "specific and limited defensive" operations from Diego Garcia and RAF Fairford while keeping Akrotiri closed to offensive strikes. Iran fired two ballistic missiles at the atoll, roughly 4,000 km from its territory, within hours of that authorisation being confirmed in March.
The legal footing stayed contested. Attorney General Lord Hermer KC had advised that the US-Israeli operation did not accord with international law, and the government acted against that advice. YouGov polling published in The Week of 22 March found 58% of Britons opposed US use of UK bases for strikes on Iran, with 21% in favour. On 23 March Starmer rejected calls for a parliamentary vote, and Jeremy Corbyn's bill to require one drew 11 co-sponsors.
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Written with AI from Lowdown's published reporting. Not individually reviewed by an editor. Updated 28 September 2026. Editorial standards.