The defense readiness condition (DEFCON) is a measure of the activation and readiness level of the United States armed forces. It describes progressive postures for use between the Joint Chiefs of Staff and the commanders of unified commands. DEFCONs are matched to the situations of military severity. Standard peacetime protocol is DEFCON 5, descending in increasingly severe situations. DEFCON 1 represents expectation of actual imminent attack, and it has never been declared. The armed forces of the United States of America consist of the United States Army United States Navy United States Air Force United States Marine Corps United States Coast Guard Note: The United States Coast Guard has both military and law enforcement functions. ... Joint Chiefs of Staff of the United States of America symbol The Joint Chiefs of Staff (JCS) is a grouping comprising the Chiefs of service of each major branch of the armed services in the United States armed forces. ...

In a national state of emergency, seven different alert conditions known as LERTCONs can be issued. They consist of five Defense Conditions and two Emergency Conditions (EMERGCONs). A state of emergency is a governmental declaration that may suspend certain normal functions of government, may work to alert citizens to alter their normal behaviors, or may order government agencies to implement emergency preparedness plans. ... An alert state is an indication of the state of readiness of the armed forces for military action or a State against terrorism. ... In U.S. military doctrine, LERTCON is an acronym standing for aLERT CONdition, and is a measure of the level of action and readiness to be taken in a given situation. ... EMERGCON (Emergency Condition) is a state of readiness that is separate from DEFCON, or defense readiness condition used by the United States. ...

Levels

DEFCON 5 

This is the condition used to designate normal peacetime military readiness. An upgrade in military preparedness is typically made by the Joint Chiefs of Staff and announced by the United States Secretary of Defense.

DEFCON 4 

This refers to normal, increased intelligence and the heightening of national security measures. Readiness remained at this level throughout most of the Cold War. During this alert level, ground combat becomes authorized. During the Cuban Missile Crisis, one of the specific conditions of escalating to level 4 prompted the military to replace training (or "dummy") tips with live nuclear warheads on all target selected ICBMs.

DEFCON 3 

This refers to an increase to force readiness above normal. Radio call signs used by American forces change to currently-classified call signs. Naval and air combat becomes authorized.

DEFCON 2 

This refers to a further increase in force readiness just below maximum readiness. It has only been declared once, during the Cuban Missile Crisis.

DEFCON 1 

This refers to maximum readiness. It is not certain whether this has ever been used, but it is reserved for imminent or ongoing attack on US military forces or US territory by a foreign military power. Use of nuclear weapons is authorized.

The United States Secretary of Defense is the head of the United States Department of Defense (DoD), concerned with the armed services and The role of the Secretary of Defense is to be the principal defense policy advisor to the President and is responsible for the formulation of general defense... For other uses, see Cold War (disambiguation). ... USAF reconnaissance photo of one of the suspected launch sites The Cuban Missile Crisis was a confrontation during the Cold War between the Cubans and the United States regarding the Soviet deployment of nuclear missiles in Cuba. ... A Minuteman III missile soars after a test launch. ... In broadcasting, a callsign or call sign (also call letters) is a unique designation for a transmitting station. ... USAF reconnaissance photo of one of the suspected launch sites The Cuban Missile Crisis was a confrontation during the Cold War between the Cubans and the United States regarding the Soviet deployment of nuclear missiles in Cuba. ...

History

Cold War

The highest alert condition the US military has been at was DEFCON 2. During the Cuban Missile Crisis on 22 October 1962, Strategic Air Command (SAC) was ordered to 2 and the rest of the US military to 3. SAC remained at 2 until 15 November. USAF reconnaissance photo of one of the suspected launch sites The Cuban Missile Crisis was a confrontation during the Cold War between the Cubans and the United States regarding the Soviet deployment of nuclear missiles in Cuba. ... October 22 is the 295th day of the year (296th in leap years) in the Gregorian Calendar, with 70 days remaining. ... 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar). ... For the film of the same name, see Strategic Air Command (film) The Strategic Air Command (SAC) was the operational establishment of the United States Air Force in charge of Americas bomber-based and ballistic missile-based strategic nuclear arsenal from 1946 to 1992. ... November 15 is the 319th day of the year (320th in leap years) in the Gregorian Calendar, with 46 days remaining. ...

For much of the Cold War, US ICBM sites were always at DEFCON 4 rather than 5.

It should be further noted that SAC's move to DEFCON 2 during the Cuban Missile Crisis was precipitated by Generals Thomas S. Power and Curtis LeMay, and it was done without consulting the executive branch. A General is an officer of high military rank. ... General Thomas Sarsfield Power was commander in chief of the Strategic Air Command and an active military flier for more than 30 years. ... Curtis Emerson LeMay (November 15, 1906 – October 1, 1990) was a General in the United States Air Force and the vice presidential running mate of independent candidate George C. Wallace in 1968. ... The executive is the branch of a government charged with implementing, or executing, the law and running the day-to-day affairs of the government or state. ...

Yom Kippur War

Higher alert conditions were also ordered during the 1973 Yom Kippur War. While the US military was technically at DEFCON 3 status during the Yom Kippur War, in certain theaters it operated under DEFCON 2 conditions as a show-of-force to repel Soviet naval vessels from entering the Bosporus Strait. For example, Pershing I missiles in West Germany were prepared for use. Combatants Israel Egypt, Syria, Jordan, Iraq Commanders Moshe Dayan, David Elazar, Ariel Sharon, Shmuel Gonen, Benjamin Peled, Israel Tal, Rehavam Zeevi, Aharon Yariv, Yitzhak Hofi, Rafael Eitan, Abraham Adan, Yanush Ben Gal Saad El Shazly, Ahmad Ismail Ali, Hosni Mubarak, Mohammed Aly Fahmy, Anwar Sadat, Abdel Ghani el-Gammasy, Abdul... Fatih Sultan Mehmed Bridge over the Bosporus seen from over Rumelihisarı This article is about the strait; Bosphorus is also a Turkish Boğaziçi or İstanbul Boğazı) is a strait that separates the European part (Rumeli) of Turkey from its Asian part (Anadolu...

Gulf War

Some declassified documents suggest that DEFCON 1 was ordered and attained during the Gulf War of 1991.[1] The exact time and date quoted as "USCINCCENT AND ALL COMPONENTS ATTAINED DEFCON 1 AT 0925C" dated 19 JAN 1991.[2] (USCINCCENT = United States Commander in Chief Central Command, General Norman Schwarzkopf). This is specific to a limited geographic area and not a general DEFCON-1 for all forces. Combatants UN Coalition Republic of Iraq Commanders Norman Schwarzkopf Saddam Hussein Strength 883,863 360,000 Casualties 378 dead, 1,000 wounded 25,000 dead, 75,000 wounded The Gulf War (2 August 1990 – 28 February 1991) was a conflict between Iraq and a coalition force of approximately 30 nations... General H. Stormin Norman Schwarzkopf KCB (born August 22, 1934) is a retired United States Army general who, while he served as Commander-in-Chief (now known as Combatant Commander) of U.S. Central Command, was commander of the Coalition Forces in the Gulf War of 1991. ...

September 11

The third time the United States reached DEFCON 3 was during the September 11, 2001 attacks. A sequential look at United Flight 175 crashing into the south tower of the World Trade Center The September 11, 2001 attacks (often referred to as 9/11—pronounced nine eleven or nine one one) consisted of a series of coordinated terrorist[1] suicide attacks upon the United States, predominantly...

Operations

The DEFCON level is controlled primarily by the President and the Joint Chiefs of Staff, and each DEFCON level defines specific security, activation and response scenarios for the troops in question. For other uses, see President of the United States (disambiguation). ... Joint Chiefs of Staff of the United States of America symbol The Joint Chiefs of Staff (JCS) is a grouping comprising the Chiefs of service of each major branch of the armed services in the United States armed forces. ...

Different branches of the armed forces (like the Army, Navy, Air Force) and different bases or command groups can be activated at different defense conditions. The United States Army is the largest branch of the United States armed forces and has primary responsibility for land-based military operations. ... USN redirects here. ... Aircraft of the 379th Air Expeditionary Wing and coalition counterparts stationed together at Al Udeid Air Base, Qatar, in southwest Asia, fly over the desert. ...

See also

• Homeland Security Advisory System
• BIKINI states - Status codes used by British armed forces
• Joint Terrorist Analysis Centre - Determines terrorist threat level in the UK

In the United States, the Homeland Security Advisory System is a color-coded terrorism threat advisory scale. ... The BIKINI state is an indication of an alert state as used by the British government, specifically the Ministry of Defence, to warn of non-specific forms of terrorist activity. ... The Joint Terrorist Analysis Centre (JTAC) advises the United Kingdom government on terrorist threat levels and related security considerations. ...

References

• DEFCON DEFense CONdition