Iran Conflict — 2026-03-21

Iran Fires Two IRBMs at Diego Garcia, Revealing Previously Denied Long-Range Missile Capability

Iran launched two intermediate-range ballistic missiles at Diego Garcia, the US-UK base in the Indian Ocean approximately 4,000km from Iranian territory. One missile failed in flight; a US warship fired an SM-3 interceptor at the other. Neither struck the base. The attack revealed Iran possesses missile capabilities double its officially stated 2,000km limit, a capability Tehran had explicitly denied. The strike came shortly before Britain authorized US use of Diego Garcia for Hormuz defensive operations.

Analysis
Prior INTSUMs tracked Iran's missile capability at the officially declared 2,000km range. The Diego Garcia strike at 4,000km represents a capabilities revelation: Iran maintained covert IRBM programs despite years of arms control assertions to the contrary.

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