From Citizendium, the Citizens' Compendium
- Air defense artillery : A combat arms branch of the United States Army, responsible for defending ground forces and the continental United States against aircraft and missile attack
- Ballistic missile defense : A combination of sensors, command and control systems, and missile/warhead kill mechanisms that protect a region, or, in the case of the U.S., theaters of operations as well as the nation proper.
- Terminal High Altitude Area Defense (missile) : An anti-ballistic missile, developed by the U.S. Army, intended as the high-altitude tier of a layered theater ballistic missile defense system
- MIM-104 Patriot : Missile originally developed for medium-to-high altitude aircraft interception (SAM) use, which, while retaining that capability, is now optimized as an anti-ballistic missile (ABM) for relatively small but critical areas. The SAM versions have explosive warheads but the ABM is hit-to-kill.
- SPY-2 : A supplementary radar for AEGIS battle management system ships, which adds theater ballistic missile defense engagement for the RIM-161 Standard SM-3 missile