Nuclear warfare, also known as atomic warfare, is a military conflict or prepared political strategy that deploys nuclear weaponry. Nuclear weapons are weapons of mass destruction; in contrast to conventional warfare, nuclear warfare can produce destruction in a much shorter time and can have a long-lasting radiological result. A major nuclear exchange would likely have long-term effects, primarily from the fallout released, and could also lead to secondary effects, such as "nuclear winter", nuclear famine, and societal collapse. A global thermonuclear war with Cold War-era stockpiles, or even with the current smaller stockpiles, may lead to various scenarios including the extinction of the human species.
Mutual assured destruction (MAD) is a doctrine of military strategy and national security policy which posits that a full-scale use of nuclear weapons by an attacker on a nuclear-armed defender with second-strike capabilities would result in the complete annihilation of both the attacker and the defender. It is based on the theory of rational deterrence, which holds that the threat of using strong weapons against the enemy prevents the enemy's use of those same weapons. The strategy is a form of Nash equilibrium in which, once armed, neither side has any incentive to initiate a conflict or to disarm.
World War III, World War 3, WWIII, WW3, or the Third World War are the names given to a hypothetical global conflict subsequent to World War I and World War II. The term has been in use since as early as 1941. Some apply it loosely to limited or more minor conflicts such as the Cold War or the war on terror. In contrast, others assume that such a conflict would surpass prior world wars in both scope and destructive impact.
Building on major scientific breakthroughs made during the 1930s, the United Kingdom began the world's first nuclear weapons research project, codenamed Tube Alloys, in 1941, during World War II. The United States, in collaboration with the United Kingdom, initiated the Manhattan Project the following year to build a weapon using nuclear fission. The project also involved Canada. In August 1945, the atomic bombings of Hiroshima and Nagasaki were conducted by the United States, with British consent, against Japan at the close of that war, standing to date as the only use of nuclear weapons in hostilities.
The nuclear arms race was an arms race competition for supremacy in nuclear warfare between the United States, the Soviet Union, and their respective allies during the Cold War. During this same period, in addition to the American and Soviet nuclear stockpiles, other countries developed nuclear weapons, though none engaged in warhead production on nearly the same scale as the two superpowers.
Canada has not officially maintained and possessed weapons of mass destruction since 1984 and, as of 1998, has signed treaties repudiating possession of them. Canada ratified the Geneva Protocol in 1930 and the Nuclear Non-proliferation Treaty in 1970.
The "Revolt of the Admirals" was a policy and funding dispute within the United States government during the Cold War in 1949, involving a number of retired and active-duty United States Navy admirals. These included serving officers Admiral Louis E. Denfeld, Chief of Naval Operations, and Vice Admiral Gerald F. Bogan, as well as Fleet Admirals Chester Nimitz and William Halsey, senior officers during World War II.
The Single Integrated Operational Plan (SIOP) was the United States' general plan for nuclear war from 1961 to 2003. The SIOP gave the President of the United States a range of targeting options, and described launch procedures and target sets against which nuclear weapons would be launched. The plan integrated the capabilities of the nuclear triad of strategic bombers, land-based intercontinental ballistic missiles (ICBM), and sea-based submarine-launched ballistic missiles (SLBM). The SIOP was a highly classified document, and was one of the most secret and sensitive issues in U.S. national security policy.
Operation Unthinkable was the name given to two related possible future war plans developed by the British Chiefs of Staff Committee against the USSR during 1945. The plans were never implemented. The creation of the plans was ordered by British Prime Minister Winston Churchill in May 1945 and developed by the British Armed Forces' Joint Planning Staff in May 1945 at the end of World War II in Europe.
Able Archer 83 was a military exercise conducted by NATO that took place in November 1983. It simulated a period of heightened nuclear tensions between NATO and the Warsaw Pact, leading to concerns that it could have been mistaken for a real attack by the Soviet Union. The exercise is considered by some to be one of the closest moments the world came to nuclear war during the Cold War. It was the annual Able Archer exercise conducted in November 1983. The purpose for the exercise, like previous years, was to simulate a period of conflict escalation, culminating in the US military attaining a simulated DEFCON 1 coordinated nuclear attack. The five-day exercise, which involved NATO commands throughout Western Europe, was coordinated from the Supreme Headquarters Allied Powers Europe (SHAPE) headquarters in Casteau, Belgium.
The United States was the first country to manufacture nuclear weapons and is the only country to have used them in combat, with the bombings of Hiroshima and Nagasaki in World War II. Before and during the Cold War, it conducted 1,054 nuclear tests, and tested many long-range nuclear weapons delivery systems.
Atomic spies or atom spies were people in the United States, the United Kingdom, and Canada who are known to have illicitly given information about nuclear weapons production or design to the Soviet Union during World War II and the early Cold War. Exactly what was given, and whether everyone on the list gave it, are still matters of some scholarly dispute. In some cases, some of the arrested suspects or government witnesses had given strong testimonies or confessions which they recanted later or said were fabricated. Their work constitutes the most publicly well-known and well-documented case of nuclear espionage in the history of nuclear weapons. At the same time, numerous nuclear scientists wanted to share the information with the world scientific community, but this proposal was firmly quashed by the United States government. It is worth noting that many scientists who worked on the Manhattan Project were deeply conflicted about the ethical implications of their work, and some were actively opposed to the use of nuclear weapons.
Seven Days to the River Rhine was a top-secret military simulation exercise developed at least since 1964 by the Warsaw Pact. It depicted the Soviet Bloc's vision of a seven-day nuclear war between NATO and Warsaw Pact forces.
The Report on the International Control of Atomic Energy was written by a committee chaired by Dean Acheson and David Lilienthal in 1946 and is generally known as the Acheson–Lilienthal Report or Plan. The report was an important American document that appeared just before the intensification of the early Cold War. It proposed the international control of nuclear weapons and the avoidance of future nuclear warfare. A version, the Baruch Plan, was vetoed by the Soviets at the United Nations.
World War III, sometimes abbreviated to WWIII, is a common theme in popular culture. Since the 1940s, countless books, films, and television programmes have used the theme of nuclear weapons and a third global war. The presence of the Soviet Union as an international rival armed with nuclear weapons created persistent fears in the United States and vice versa of a nuclear World War III, and popular culture at the time reflected those fears. The theme was also a way of exploring a range of issues beyond nuclear war in the arts. U.S. historian Spencer R. Weart called nuclear weapons a "symbol for the worst of modernity."
Substantial debate exists over the ethical, legal, and military aspects of the atomic bombings of Hiroshima and Nagasaki on 6 August and 9 August 1945 at the close of World War II (1939–45).
This timeline of nuclear weapons development is a chronological catalog of the evolution of nuclear weapons rooting from the development of the science surrounding nuclear fission and nuclear fusion. In addition to the scientific advancements, this timeline also includes several political events relating to the development of nuclear weapons. The availability of intelligence on recent advancements in nuclear weapons of several major countries is limited because of the classification of technical knowledge of nuclear weapons development.
Proud Prophet was a war game played by the United States that began on June 20, 1983, and was designed by Thomas Schelling. The simulation was played in real time during the Cold War. Proud Prophet was essentially played to test out various proposals and strategies, in response to the Soviet Union's military buildup. There were advocates for a number of strategies, which varied from demonstration nuclear attacks, limited nuclear war, and decapitation attacks. It was not possible for the United States to pursue each of these strategies. President Ronald Reagan and his administration were faced with the dilemma of figuring out how the United States should respond to the Soviet Union's large nuclear programs, while finding which strategy would be most effective.
A nuclear close call is an incident that might have led to at least one unintended nuclear detonation or explosion, but did not. These incidents typically involve a perceived imminent threat to a nuclear-armed country which could lead to retaliatory strikes against the perceived aggressor. The damage caused by international nuclear exchange is not necessarily limited to the participating countries, as the hypothesized rapid climate change associated with even small-scale regional nuclear war could threaten food production worldwide—a scenario known as nuclear famine. There have also been a number of accidents involving nuclear weapons, such as crashes of nuclear armed aircraft.
United States war plans for a conflict with the Soviet Union (USSR) were formulated and revised on a regular basis between 1945 and 1950. Although most were discarded as impractical, they nonetheless would have served as the basis for action had a conflict occurred. At no point was it considered likely that the Soviet Union or United States would resort to war, only that one could potentially occur as a result of a miscalculation. Planning was conducted by agencies of the Joint Chiefs of Staff, in collaboration with planners from the United Kingdom and Canada.
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