How far can Iran’s ballistic missiles reach? A defense expert explains how the missiles work, and what Iran can and can’t hit

Iran launched two missiles, possibly modified versions of this Khorramshahr ballistic missile, at the island of Diego Garcia. Iranian Defense Ministry via AP

Iran fired two ballistic missiles on March 20, 2026, at the Indian Ocean island of Diego Garcia, which hosts a strategically important joint U.S.-U.K. military base, according to U.S., U.K. and Israeli officials. One missile broke apart during flight, and the other appears to have been destroyed by U.S. missile defenses.

Iran has denied responsibility for the launches.