Following up on my DEFCON article for Air&Space, following is a working outline I put together during my
research. It catalogs dozens of Cold War alerts and false alarms along with the small number (four) of global DEFCON scares.
Out of all the events listed below, I regard five as particularly chilling: the "Black Forest Incident" of 1961; Soviet concerns about NATO's Able Archer exercise in 1983; several showdowns during the Cuban Missile Crisis of 1962; a US-Soviet naval faceoff during the 1973 Yom Kippur War; and a false alert at Cheyenne Mountain in November 1979.
The takeaway for me: DEFCON alerts are not the whole story, although it was the focus of my article. Among the incidents that came closest to nuclear war, in several the events moved so quickly (spanning less than ten minutes) that no DEFCON change was ordered.
= = =
A. Significant Cold War alerts that happened prior to
adoption of the five-level DEFCON scale in 1959 by Canada and the US
• June 25, 1950: Joint Chiefs of Staff
called a general alert for the USAF, based on concerns that invasion
of North Korea could be part of general war plan by Soviets
• May 6, 1955: Yellow Alert triggered (air defense emergency, attack considered likely), when
a flight of 13 B-47s returning from Canada were thought to be enemy
bombers
• November 1956: Some US nuclear
forces in Europe were activated during the Hungarian revolution, coincidentally as
the Suez Crisis was winding down
B. Times when the US raised global DEFCON
levels at direction of National Command Authority (NCA)
• May 1960: US forces went to DEFCON
Three, at direction of the Secretary of Defense; most likely as a
signal to the Soviets in response to failure of four-power talks in
Paris
• October 1962, Cuban Missile Crisis:
SAC went to DEFCON Two, other global US forces went to DEFCON Three,
except for US nuclear forces in Europe
• October 1973, “Middle East
Contingency Alert”: US forces went to “DEFCON Three Worldwide, no
exceptions”: US Sixth Fleet sustained the higher readiness into
November due to tensions near Crete with Soviet Fifth Eskadra
• Attacks on September 11, 2001:
DEFCON Three called, national emergency declared, and FPCON raised to
Delta. Modified SCATANA procedures (aka ESCAT) authorized military to
direct FAA to ground all unauthorized domestic flights
C. Events during which
regional US forces raised their DEFCON levels (Partial list)
• Vietnam War: US Navy in Western
Pacific went to DEFCON Three for duration
• August 1976, “Panmunjom Incident:”
killing of two US officers; US forces in Korea went to DEFCON Three;
accompanied by military-backed action to cut down disputed tree in
DMZ
• October 26, 1979, killing of South
Korean President Park Chung Hee: US Forces in Korea increased
readiness from DEFCON Four to DEFCON Three
• January 1991, Operation Desert
Storm: DEFCON Two ordered by NCA (National Command Authority) for US forces near Iraq; at least
one ship raised its level to DEFCON One
D. Events since 1959 that triggered a
higher alert or readiness precaution, but apparently not a DEFCON change
• July 1962: Berlin Crisis, call-up of
infantry reserves
• March 1963: Overflight of Alaska by
two Soviet TU-16s prompted an attempt at interception by
nuclear-armed US interceptors
• November 1963, day of JFK
assassination: Anecdotally, some SAC bases went to higher level of
defense posture, even launching bombers to avoid being destroyed on the
ground
• September 1963: US interceptors met
Soviet bombers near US airspace
• June 1967, Six Day War: Israeli
attack on USS Liberty led briefly to mistaken belief that attack was
by Soviets
• January 1968: North Korean capture
of the USS Pueblo; the commander of US Forces, Korea considered increasing from DEFCON Four to DEFCON Three, but didn't authorize it
• August 1968: Soviet invasion of
Czechoslovakia; Soviets went on elevated alert fearing a NATO
response
• April 1969: North Korean shoot-down
of EC-121 intelligence-gathering plane
• September 1969: Libyan coup.
Presence of Soviet fleet offshore Libya discouraged US or British
intervention in support of deposed king
• October 1969: SAC forces went to
higher alert in “JCS Joint Readiness Test”, apparently done to
send a signal to Soviets and North Vietnam that they should negotiate
about the Vietnam War. Coincidentally, earlier that year, Soviet and
Chinese forces were skirmishing in a border dispute
that could have led to a nuclear strike
• September 1970, Jordanian “Black
September” crisis: US forces near Jordan and Syria on elevated
alert
• December 1971, Indian-Pakistan
Crisis: US and Soviet naval forces in Indian Ocean experienced
friction
• August 1978: SAC bombers dispersed
from regular bases after news that Soviet submarines were unusually
close to US East Coast
• Attempted assassination of President
Reagan, March 30, 1981: Secretary of Defense directed that SAC crews
be kept closer to aircraft (apparently was a change in Defense Posture, not a change in DEFCON level)
• January to November 1983: Series of
events and misunderstandings that apparently convinced Soviet leaders
to fear a US first strike. Risk of accidental nuclear war peaked
during November's Able Archer exercise by NATO
• May 1987: Iraqi jets attacked USS
Stark
• November 2010 shelling of Yeonpyeong
Island by North Korea, and retaliatory shelling by South Korea
E. Short-lived alerts or false alarms that
could have elevated into a nuclear strike
• October 5, 1960: BMEWS radar at
Thule AFB registered rising moon as missile attack and B-47 crews
were scrambled at some bases (possibly Coco-level alert)
• May 28, 1961: Radicals of the
“American Republican Army” dynamited three microwave towers in
Idaho and Montana, creating interruptions in SAC's alert network and
briefly causing concerns that this could be pre-attack sabotage by the Soviets. (That would be significant, because most analysts predicted that any first strike would begin with sabotage by the enemy.) This attack could have fed into initial SAC concerns about the following event, a
shutdown of strategic communications believed impossible:
• November 24, 1961, “Black Forest Incident": a telephone technician's error led to complete failure of a critical microwave link near Colorado Springs. This cut off NORAD-SAC communications and
missile-warning data from Thule AFB to Ent AFB and other SAC
installations. SAC sent an alert to bomber crews to prepare for takeoff, but also used short-wave radio links to determine no attack had taken place. (Why that name? The microwave relay that failed was located on Black Forest Road)
• False alerts during Cuban Missile
Crisis: Radar display erroneously indicated missile launch from Cuba
in the direction of Tampa, Florida; also, false reports of intruders
breaking into SAC airbases
• 1965 Northeast Blackout: “Bomb
Alert System” generated false signals indicating nuclear
detonations in Arizona and South Carolina
• October 1979 through June 1980:
false alerts at NORAD due to variety of problems with sensors,
interpretation, and computers. These led to an elevated Defense
Posture at SAC
• December 28, 1984: a Soviet sub-launched cruise missile
overflew Norway, and triggered warnings in the West