The LGM-118 Peacekeeper, originally known as the MX for "Missile, Experimental", was a MIRV-capable intercontinental ballistic missile (ICBM) produced and deployed by the United States from 1985 to 2005. The missile could carry up to 12 Mk.21 reentry vehicles, although treaty-limited to 10, each armed with a 300-kiloton W87 warhead. Initially, 100 MX ICBMs were planned to be built and deployed, but budgetary concerns eliminated the final procurement and only 50 entered service. Disarmament treaties signed after the Peacekeeper's development concluded in its eventual withdrawal from service in 2005.
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