The following is the Congressional Research Service, Defense Primer: LGM-35A Sentinel Intercontinental Ballistic Missile on Jan. 10, 2023.
From the report
The LGM-35A Sentinel is expected to replace the Minuteman III (MMIII) Intercontinental Ballistic Missile (ICBM) in the U.S. nuclear force structure. MMIII has served as the ground-based leg of the U.S. nuclear triad—land-based ballistic missiles, submarine-launched ballistic missiles, and nuclear-capable bombers—since 1970. The Air Force...