DEFCON stands for Defense Readiness Condition. It is the United States military’s five-tier system for signaling the level of threat and corresponding readiness posture, ranging from DEFCON 5 (normal readiness) to DEFCON 1 (maximum readiness for imminent or ongoing war).
Key points:
- Origin: The DEFCON system was established in 1959 by the Joint Chiefs of Staff during the Cold War to standardize readiness across U.S. forces.
- Levels and meanings:
- DEFCON 5: Normal readiness, least alert.
- DEFCON 4: Increased force protection and security measures.
- DEFCON 3: Round-the-clock readiness; forces can mobilize quickly.
- DEFCON 2: Near-term readiness; rapid deployment possible.
- DEFCON 1: Maximum readiness; imminent or ongoing threat of nuclear war.
- Operational use: Changes in DEFCON levels trigger specific procedures and actions across military commands, though many details are classified and the exact steps can vary by context.
If you’d like, I can summarize the historical moments when DEFCON levels were raised and how the public perceived those transitions, or provide quick comparisons to similar national alert systems in other countries.
