Nuclear close calls
A nuclear close call is an incident that might have led to at least one nuclear explosion, but did not. They can be split into intentional use and unintentional use close calls.
Intentional use close calls may occur during increased military tensions involving one or more nuclear states. They may be a threat made by the state, or an attack upon the state. They may also come from nuclear terrorism.
Unintentional use close calls may occur due to equipment failure. Common examples are strategic bombers accidentally dropping or crashing with nuclear bombs, or early warning systems mistaking phenomena such as weather events or non-nuclear rocket launches for an ICBM first strike and therefore recommending a second strike.
Though exact details on many nuclear close calls are hard to come by, the analysis of particular cases has highlighted the importance of a variety of factors in preventing accidents. At an international level, this includes the importance of context and outside mediation; at the national level, effectiveness in government communications, and involvement of key decision-makers; and, at the individual level, the decisive role of individuals in following intuition and prudent decision-making, often in violation of protocol.
A possible example of an accident that did result in a nuclear explosion is the 2019 Nyonoksa radiation accident in Russia.
Any nuclear exchange carries the possibility of rapid climate change, threatening global food production: nuclear famine.
Despite reduction of nuclear arms and lower tensions after the end of the Cold War, estimated nuclear warhead stockpiles total roughly 15,000 worldwide, with the United States and Russia holding 90% of the total.
Intentional use close calls
Intentional close calls may occur during increased military tensions involving one or more nuclear states. They may be a threat made by the state, or an attack upon the state. They may also come from nuclear terrorism.1950–1953: Korean War
During the Korean War, the US considered nuclear attacks on North Korea and Manchuria, in response to involvement from the People's Volunteer Army from China. Mark 4 nuclear bombs, lacking their fissile pits, were deployed to Guam and Okinawa. Boeing B-29 Superfortresses were stationed in Kadena Air Base, Okinawa, and flew practice bombing runs with dummy nuclear or conventional bombs against North Korean targets.The US also considered strikes on Soviet Air Force bases in the Russian Far East. The Artem air base was the most immediate.
1954: First Indochina War
During the Battle of Dien Bien Phu, at the request of the French, the US considered tactical nuclear weapons use against the Viet Minh. US strategic bombers stationed in the Philippines or Okinawa, as well as carrier aircraft in the Seventh Fleet, were considered for a strike using three tactical nuclear bombs, possibly Mark 7s.1956: Suez Crisis
During the Suez Crisis, the North American Aerospace Defense Command received a number of simultaneous reports, including unidentified aircraft over Turkey, Soviet MiG-15 fighters over Syria, a downed British Canberra medium bomber, and unexpected maneuvers by the Soviet Black Sea Fleet through the Dardanelles that appeared to signal a Soviet offensive. Considering previous Soviet threats to use conventional missiles against France and the United Kingdom, U.S. forces believed these events could trigger a NATO nuclear strike against the Soviet Union. In fact, all reports of Soviet action turned out to be erroneous, misinterpreted, or exaggerated. The perceived threat was due to a coincidental combination of events, including a wedge of swans over Turkey, a fighter escort for Syrian President Shukri al-Quwatli returning from Moscow, a British bomber brought down by mechanical issues, and scheduled exercises of the Soviet fleet.1958: Second Taiwan Strait Crisis
characterized the Second Taiwan Strait Crisis as "the first serious nuclear crisis". In this conflict, the People's Republic of China shelled the islands of Kinmen and the Matsu Islands along the east coast of mainland China in an attempt to probe the extent of the United States military defense of Taiwan's sovereign territory. This was an ultimately failed preemptive strike prior to an attempted invasion of Taiwan, where the Republic of China's military forces and political apparatuses, known as the Kuomintang, had been exiled since the end of the Chinese Civil War in 1949. A naval battle also took place around Dongding Island when the ROC Navy repelled an attempted amphibious landing by the PRC Navy.1962: Cuban Missile Crisis
Soviet nuclear weapons in Cuba
Under Operation Anadyr, the Soviet Union deployed both strategic and tactical nuclear weapons in Cuba, totalling 158 warheads. Of these, 80 were for use by the 9K52 Luna-M nuclear rocket artillery/short-range ballistic missile system, and 12 were for use by the FKR-1 cruise missile. At least one unit of the latter was targeted at the US Guantanamo Bay Naval Base on the island of Cuba.US false alarm at interceptor airbase
During the Cuban Missile Crisis, United States military planners expected that sabotage operations might precede any nuclear first strike by the Soviet Union. Around midnight on 25 October 1962, a guard at the Duluth Sector Direction Center in Minnesota saw a figure climbing the security fence. He shot at it and activated the sabotage alarm, which automatically set off similar alarms at other bases in the region. At Volk Field in Wisconsin, a faulty alarm system caused the klaxon to sound instead, which ordered Air Defense Command nuclear-armed F-106A interceptors into the air. The pilots had been told there would be no practice alert drills and, according to political scientist Scott Sagan, "fully believed that a nuclear war was starting". Before the planes were able to take off, the base commander contacted Duluth and learned of the error. An officer in the command center drove his car onto the runway, flashing his lights and signaling to the aircraft to stop. The intruder was discovered to be a bear.Sagan writes that the incident raised the dangerous possibility of an ADC interceptor accidentally shooting down a Strategic Air Command bomber. Interceptor crews had not been given full information by SAC of plans to move bombers to dispersal bases or the classified routes flown by bombers on continuous alert as part of Operation Chrome Dome. Declassified ADC documents later revealed that "the incident led to changes in the alert Klaxon system to prevent a recurrence".