国防入门：核指挥、控制与通信（NC3）

https:/crsreports.congress.gov Updated May 1,2025Defense Primer:Nuclear Command,Control,and Communications(NC3)The Department of Defense(DOD)is replacing many elements of the U.S.nuclear command,control,and communications(NC3)architecture as part of the United States ongoing efforts to recapitalize its nuclear forces.This architecturecomposed of what some estimate as 204 individual ground,space,and airborne systems spread across military services,combatant commands,and DOD componentssupports the Presidents exercise of nuclear employment authority.(See CRS In Focus IF10521,Authority to Launch Nuclear Forces.)U.S.NC3 systems must operate at all times,including during and after an attack on the United States,to sense and assess the operational environment;facilitate planning and decisionmaker conferencing;and transmit orders from the President to U.S.nuclear forces:bombers in the air,ballistic missile submarines(SSBNs)underwater,and intercontinental ballistic missiles(ICBMs)deployed in silos across the Midwest.(See CRS In Focus IF10519,Defense Primer:Strategic Nuclear Forces.)The 2010,2018,and 2022 Nuclear Posture Reviews(NPRs)periodic executive branch assessments of U.S.nuclear weap