When were nuclear weapons first used in war?
Nuclear proliferation
Research into the development of nuclear weapons was initially undertaken during World War II by the United States (in cooperation with the United Kingdom and Canada), Germany, Japan, and the USSR. The United States was the first and is the only country to have used a nuclear weapon in war, when it used two bombs against Japan in August 1945. After surrendering to end the war, Germany and Japan ceased to be involved in any nuclear weapon research. In August 1949, the USSR tested a nuclear weapon, becoming the second country to detonate a nuclear bomb. The United Kingdom first tested a nuclear weapon in October 1952. France first tested a nuclear weapon in 1960. The People's Republic of China detonated a nuclear weapon in 1964. India conducted its first nuclear test in 1974, which prompted Pakistan to develop its own nuclear program and, when India conducted a second series of nuclear tests in 1998, Pakistan followed with a series of tests of its own. In 2006, North Korea conducted its first nuclear test.
History of nuclear weapons
Nuclear weapons possess enormous destructive power from nuclear fission or combined fission and fusion reactions. Building on scientific breakthroughs made during the 1930s, the United States, the United Kingdom and Canada collaborated during World War II, in what was called the Manhattan Project, to counter the suspected Nazi German atomic bomb project. In August 1945, two fission bombs were dropped on Japan, standing to date as the only use of nuclear weapons in combat. The Soviet Union started development shortly thereafter with their own atomic bomb project, and not long after that both countries developed even more powerful fusion weapons known as "hydrogen bombs".
Thermonuclear weapon
The first full-scale thermonuclear test was carried out by the United States in 1952; the concept has since been employed by most of the world's nuclear powers in the design of their weapons. The design of all modern thermonuclear weapons in the United States is known as the "Teller–Ulam configuration" for its two chief contributors, Edward Teller and Stanislaw Ulam, who developed it in 1951 for the United States, with certain concepts developed with the contribution of physicist John von Neumann. Similar devices were developed by the Soviet Union, United Kingdom, France, and China.
1958 US–UK Mutual Defence Agreement
The first British atomic bomb was successfully tested in Operation Hurricane on 3 October 1952, 
but although it was more advanced than the American bombs of 1946, Britain was still several years behind in nuclear weapons technology. The United States conducted Ivy Mike, the first nuclear test of a true thermonuclear device (also known as a hydrogen bomb). The JCAE saw little benefit for the United States from sharing technology with Britain. The Soviet Union responded with the test of Joe 4, a boosted fission weapon on 12 August 1953. This prompted President Dwight Eisenhower, who was inaugurated in January 1953, to inform the United States Congress that the McMahon Act, which he considered a "terrible piece of legislation" and "one of the most deplorable incidents in American history of which he personally felt ashamed", was obsolete.
At the three-power Bermuda Conference in December 1953, Eisenhower and Churchill discussed the possibility of the United States giving Britain access to American nuclear weapons in wartime. This came to be called Project E. There were technical and legal issues that had to be overcome before American bombs could be carried in British aircraft. The United States would have to disclose their weights and dimensions, while their delivery would require data concerning their ballistics. Further down the track, there would also be issues of custody, security and targeting. The release of such information was restricted by the McMahon Act.
Historical nuclear weapons stockpiles and nuclear tests by country
The Soviet Union developed its first nuclear weapon in 1949 and increased its nuclear stockpile rapidly until it peaked in 1986 under Mikhail Gorbachev. As Cold War tensions decreased, and after the collapse of the Soviet Union, the Soviet and Russian nuclear stockpile decreased by over 80% between 1986 and 2012.
History of nuclear weapons
In December 1979, NATO decided to deploy cruise and Pershing II missiles in Western Europe in response to Soviet deployment of intermediate range mobile missiles, and in the early 1980s, a "dangerous Soviet-US nuclear confrontation" arose. In New York on June 12, 1982, one million people gathered to protest about nuclear weapons, and to support the second UN Special Session on Disarmament. As the nuclear abolitionist movement grew, there were many protests at the Nevada Test Site. For example, on February 6, 1987, nearly 2,000 demonstrators, including six members of Congress, protested against nuclear weapons testing and more than 400 people were arrested. Four of the significant groups organizing this renewal of anti-nuclear activism were Greenpeace, The American Peace Test, The Western Shoshone, and Nevada Desert Experience.
Nuclear warfare
After World War II, nuclear weapons were also developed by the Soviet Union (1949), the United Kingdom (1952), France (1960), and the People's Republic of China (1964), which contributed to the state of conflict and extreme tension that became known as the Cold War. In 1974, India, and in 1998, Pakistan, two countries that were openly hostile toward each other, developed nuclear weapons. Israel (1960s) and North Korea (2006) are also thought to have developed stocks of nuclear weapons, though it is not known how many. The Israeli government has never admitted or denied to having nuclear weapons, although it is known to have constructed the reactor and reprocessing plant necessary for building nuclear weapons. South Africa also manufactured several complete nuclear weapons in the 1980s, but subsequently became the first country to voluntarily destroy their domestically made weapons stocks and abandon further production (1990s). Nuclear weapons have been detonated on over 2,000 occasions for testing purposes and demonstrations.
Technology during World War II
The strategic importance of the bomb, and its even more powerful fusion-based successors, did not become fully apparent until the United States lost its monopoly on the weapon in the post-war era. The Soviet Union developed and tested their first fire weapon in 1949, based partially on information obtained from Soviet espionage in the United States. Competition between the two superpowers played a large part in the development of the Cold War. The strategic implications of such a massively destructive weapon still reverberate in the 21st century.
List of states with nuclear weapons
The United Kingdom tested its first nuclear weapon ("Hurricane") in 1952. The UK had provided considerable impetus and initial research for the early conception of the atomic bomb, aided by Austrian, German and Polish physicists working at British universities who had either fled or decided not to return to Nazi Germany or Nazi controlled territories. The UK collaborated closely with the United States and Canada during the Manhattan Project, but had to develop its own method for manufacturing and detonating a bomb as U.S. secrecy grew after 1945. The United Kingdom was the third country in the world, after the United States and Soviet Union, to develop and test a nuclear weapon. Its programme was motivated to have an independent deterrent against the Soviet Union, while also maintaining its status as a great power. It tested its first hydrogen bomb in 1957 (Operation Grapple), making it the third country to do so after the United States and Soviet Union. The UK maintained a fleet of V bomber strategic bombers and ballistic missile submarines (SSBNs) equipped with nuclear weapons during the Cold War. It currently maintains a fleet of four 'Vanguard' class ballistic missile submarines equipped with Trident II missiles. In 2016, the UK House of Commons voted to renew the British nuclear weapons system with the "Dreadnought"-class submarine, without setting a date for the commencement of service of a replacement to the current system.
Nuclear arms race
Both governments spent massive amounts to increase the quality and quantity of their nuclear arsenals. Both nations quickly began the development of a hydrogen bomb and the United States detonated the first hydrogen bomb on November 1, 1952, on Enewetak, an atoll in the Pacific Ocean. Code-named "Ivy Mike", the project was led by Edward Teller, a Hungarian-American nuclear physicist. It created a cloud 100 miles wide and 25 miles high, killing all life on the surrounding islands. Again, the Soviets surprised the world by exploding a deployable thermonuclear device in August 1953 although it was not a true multi-stage hydrogen bomb. However, it was small enough to be dropped from an airplane, making it ready for use. The development of these two Soviet bombs was greatly aided by the Russian spies Harry Gold and Klaus Fuchs.
Pre-emptive nuclear strike
In the immediate aftermath of World War II, the leadership of the Soviet Union feared the United States would use its nuclear superiority to its advantage, as from 1945 to 1948 the U.S. was the only state possessing nuclear weapons. The USSR countered by rapidly developing their own nuclear weapons, surprising the US with their first test in 1949. In turn, the U.S. countered by developing the vastly more powerful thermonuclear weapon, testing their first hydrogen bomb in 1952 at Ivy Mike, but the USSR quickly countered by testing their own thermonuclear weapons, with a test in 1953 of a semi-thermonuclear weapon of the Sloika design, and in 1956, with the testing of Sakharov's Third Idea – equivalent to the Castle Bravo device. Meanwhile, tensions between the two nations rose as 1956 saw the suppression of Hungary by the Soviets; the U.S. and European nations drew certain conclusions from that event, while in the U.S., a powerful social backlash was afoot, prompted by Senator Joseph McCarthy, the House Un-American Activities Committee, and Julius and Ethel Rosenberg, U.S. citizens executed in 1953 after conviction of espionage. This atmosphere was further inflamed by the 1957 launch of Sputnik, which led to fears of Communists attacking from outer space, as well as concerns that if the Soviets could launch a device into orbit, they could equally cause a device to re-enter the atmosphere and impact any part of the planet. John F. Kennedy capitalized on this situation by emphasizing the Bomber gap and the Missile gap, areas in which the Soviets were (inaccurately) perceived as leading the United States, while heated Soviet rhetoric added to political pressure. The 1960 U-2 incident, involving Francis Gary Powers, as well as the Berlin Crisis, along with the test of the Tsar Bomba, escalated tensions still further.
Nuclear explosion
Since the Trinity test and excluding the combat use of nuclear weapons, mankind (those few nations with capability) has detonated roughly 1,700 nuclear explosions, all but 6 as tests. Of these, six were peaceful nuclear explosions. Nuclear tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout the 20th century, most nations that have developed nuclear weapons had a staged test of them. Testing nuclear weapons can yield information about how the weapons work, as well as how the weapons behave under various conditions and how structures behave when subjected to a nuclear explosion. Additionally, nuclear testing has often been used as an indicator of scientific and military strength, and many tests have been overtly political in their intention; most nuclear weapons states publicly declared their nuclear status by means of a nuclear test.
History of nuclear weapons
On March 1, 1954, the U.S. detonated its first practical thermonuclear weapon (which used isotopes of lithium as its fusion fuel), known as the "Shrimp" device of the Castle Bravo test, at Bikini Atoll, Marshall Islands. The device yielded 15 megatons, more than twice its expected yield, and became the worst radiological disaster in U.S. history. The combination of the unexpectedly large blast and poor weather conditions caused a cloud of radioactive nuclear fallout to contaminate over . 239 Marshall Island natives and 28 Americans were exposed to significant amounts of radiation, resulting in elevated levels of cancer and birth defects in the years to come.
Nuclear warfare
With the monopoly over nuclear technology broken, worldwide nuclear proliferation accelerated. The United Kingdom tested its first independent atomic bomb in 1952, followed by France in 1960 and then China in 1964. While much smaller than the arsenals of the United States and the Soviet Union, Western Europe's nuclear reserves were nevertheless a significant factor in strategic planning during the Cold War. A top-secret White Paper, compiled by the Royal Air Force and produced for the British Government in 1959, estimated that British bombers carrying nuclear weapons were capable of destroying key cities and military targets in the Soviet Union, with an estimated 16 million deaths in the Soviet Union (half of whom were estimated to be killed on impact and the rest fatally injured) "before" bomber aircraft from the U.S. Strategic Air Command reached their targets.
No first use
Pakistan, Russia, the United Kingdom, the United States, and France say they will use nuclear weapons against either nuclear or non-nuclear states only in the case of invasion or other attack against their territory or against one of their allies. Historically, NATO military strategy, taking into account the numerical superiority of Warsaw Pact conventional forces, assumed that the use of tactical nuclear weapons would have been required in defeating a Soviet invasion.
Weapon of mass destruction
The only country to have used a nuclear weapon in war is the United States, which dropped two atomic bombs on the Japanese cities of Hiroshima and Nagasaki during World War II. There are eight countries that have declared they possess nuclear weapons and are known to have tested a nuclear weapon, only five of which are members of the NPT. The eight are China, France, India, North Korea, Pakistan, Russia, the United Kingdom, and the United States.
Nuclear weapon
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb). Both bomb types release large quantities of energy from relatively small amounts of matter. The first test of a fission ("atomic") bomb released an amount of energy approximately equal to . The first thermonuclear ("hydrogen") bomb test released energy approximately equal to . A thermonuclear weapon weighing little more than can release energy equal to more than . A nuclear device no larger than traditional bombs can devastate an entire city by blast, fire, and radiation. Since they are weapons of mass destruction, the proliferation of nuclear weapons is a focus of international relations policy.
History of nuclear weapons
The atomic bombings of Hiroshima and Nagasaki and the end of World War II quickly followed the 1945 Trinity nuclear test, and the Little Boy device was detonated over the Japanese city of Hiroshima on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people. Subsequently, the world’s nuclear weapons stockpiles grew.
Nuclear arms race
The first nuclear weapon was created by the United States of America. During the Second World War and was developed to be used against the Axis powers. Scientists of the Soviet Union were aware of the potential of nuclear weapons and had also been conducting research on the field.
History of nuclear weapons
As a show of political strength, the Soviet Union tested the largest-ever nuclear weapon in October 1961, the massive Tsar Bomba, which was tested in a reduced state with a yield of around 50 megatons—in its full state it was estimated to have been around 100 Mt. The weapon was largely impractical for actual military use, but was hot enough to induce third-degree burns at a distance of 62 mi (100 km) away. In its full, dirty, design it would have increased the amount of worldwide fallout since 1945 by 25%.
History of the anti-nuclear movement
On August 6, 1945, towards the end of World War II, the Little Boy device was detonated over the Japanese military city of Hiroshima. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings (including the headquarters of the 2nd General Army and Fifth Division) and killed approximately 75,000 people, among them 20,000 Japanese soldiers and 20,000 Korean slave laborers. Detonation of the Fat Man device exploded over the Japanese industrial city of Nagasaki three days later after Hiroshima, destroying 60% of the city and killing approximately 35,000 people, among them 23,200-28,200 Japanese munitions workers, 2,000 Korean slave laborers, and 150 Japanese soldiers. The two bombings remains the only events where nuclear weapons have been used in combat. Subsequently, the world's nuclear weapons stockpiles grew.
Plutonium
Producing plutonium in useful quantities for the first time was a major part of the Manhattan Project during World War II that developed the first atomic bombs. The Fat Man bombs used in the Trinity nuclear test in July 1945, and in the bombing of Nagasaki in August 1945, had plutonium cores. Human radiation experiments studying plutonium were conducted without informed consent, and several criticality accidents, some lethal, occurred after the war. Disposal of plutonium waste from nuclear power plants and dismantled nuclear weapons built during the Cold War is a nuclear-proliferation and environmental concern. Other sources of plutonium in the environment are fallout from numerous above-ground nuclear tests, now banned.
Nuclear arms race
The People's Republic of China became the fifth nuclear power on October 16, 1964 when it detonated a 25 kiloton uranium-235 bomb in a test codenamed 596 at Lop Nur. In the late 1950s, China began developing nuclear weapons with substantial Soviet assistance in exchange for uranium ore. However, the Sino-Soviet ideological split in the late 1950s developed problems between China and the Soviet Union. This caused the Soviets to cease helping China develop nuclear weapons. However, China continued developing nuclear weapons without Soviet support and made remarkable progress in the 1960s. Due to Soviet/Chinese tensions, the Chinese might have used nuclear weapons against either the United States or the Soviet Union in the event of a nuclear war between the United States and the Soviet Union. During the Cold War, the Chinese nuclear deterrent consisted of gravity bombs carried aboard H-6 bomber aircraft, missile systems such as the DF-2, DF-3, and DF-4, and in the later stages of the Cold War, the Type 092 ballistic missile submarine. On June 14, 1967, China detonated its first hydrogen bomb.
Nuclear arms race
Shortly after the end of the Second World War in 1945, the United Nations was founded. During the United Nation's first General Assembly in London in January 1946, they discussed the future of Nuclear Weapons and created the United Nations Atomic Energy Commission. The goal of this assembly was to eliminate the use of all Nuclear weapons. The United States presented their solution, which was called the Baruch Plan. This plan proposed that there should be an international authority that controls all dangerous atomic activities. The Soviet Union disagreed with this proposal and rejected it. The Soviets' proposal involved universal nuclear disarmament. Both the American and Soviet proposals were refused by the UN.
Nuclear weapons of the United States
Since this path was chosen, the United States was, in its early days, essentially an advocate for the prevention of nuclear proliferation, though primarily for the reason of self-preservation. A few years after the USSR detonated its first weapon in 1949, though, the U.S. under President Dwight D. Eisenhower sought to encourage a program of sharing nuclear information related to civilian nuclear power and nuclear physics in general. The Atoms for Peace program, begun in 1953, was also in part political: the U.S. was better poised to commit various scarce resources, such as enriched uranium, towards this peaceful effort, and to request a similar contribution from the Soviet Union, who had far fewer resources along these lines; thus the program had a strategic justification as well, as was later revealed by internal memos. This overall goal of promoting civilian use of nuclear energy in other countries, while also preventing weapons dissemination, has been labeled by many critics as contradictory and having led to lax standards for a number of decades which allowed a number of other nations, such as China and India, to profit from dual-use technology (purchased from nations other than the U.S.).
Cold War (1953–1962)
Khrushchev's attempt to introduce a nuclear 'doctrine of deterrence' into Soviet military thought failed. Discussion of nuclear war in the first authoritative Soviet monograph on strategy since the 1920s, Marshal Vasilii Sokolovskii's "Military Strategy" (published in 1962, 1963, and 1968) and in the 1968 edition of "Marxism-Leninism on War and the Army", focused upon the use of nuclear weapons for fighting rather than for deterring a war. Should such a war break out, both sides would pursue the most decisive aims with the most forceful means and methods. Intercontinental ballistic missiles and aircraft would deliver massed nuclear strikes on the enemy's military and civilian objectives. The war would assume an unprecedented geographical scope, but Soviet military writers argued that the use of nuclear weapons in the initial period of the war would decide the course and outcome of the war as a whole. Both in doctrine and in strategy, the nuclear weapon reigned supreme.
Armed Forces Special Weapons Project
Nuclear weapons were developed during World War II by the Manhattan Project, a major research and development effort led by the United States, with participation from the United Kingdom and Canada. From 1942 to 1946, it was under the direction of Major General Leslie R. Groves, Jr., of the US Army Corps of Engineers. It created a network of production facilities, most notably for uranium enrichment at Oak Ridge, Tennessee, plutonium production at Hanford, Washington and weapons research and design at the Los Alamos Laboratory in Los Alamos, New Mexico. The nuclear weapons that were developed were used in the atomic bombings of Hiroshima and Nagasaki in August 1945.
Arms race
A nuclear arms race developed during the Cold War, an intense period between the Soviet Union and the United States and some other countries. This was one of the main causes that began the cold war, and perceived advantages of the adversary by both sides (such as the "missile gap" and “bomber gap”) led to large spending on armaments and the stockpiling of vast nuclear arsenals. Proxy wars were fought all over the world (e.g. in the Middle East, Korea, Vietnam) in which the superpowers' conventional weapons were pitted against each other. After the dissolution of the Soviet Union and the end of the Cold War, tensions decreased and the nuclear arsenal of both countries were reduced.
Nuclear arms race
In 1952, the United Kingdom became the third nation to possess nuclear weapons when it detonated an atomic bomb in Operation Hurricane on October 3, 1952, which had a yield of 25 kilotons. Despite major contributions to the Manhattan Project by both Canadian and British governments, the U.S. Congress passed the Atomic Energy Act of 1946, which prohibited multi-national cooperation on nuclear projects. The McMahon Act fueled resentment from British scientists and Winston Churchill, as they believed that there were agreements regarding post-war sharing of nuclear technology, and led to Britain developing its own nuclear weapons. Britain did not begin planning the development of their own nuclear weapon until January 1947. Because of Britain’s small size, they decided to test their bomb on the Monte Bello Islands, off the coast of Australia. Following this successful test, under the leadership of Churchill, Britain decided to develop and test a hydrogen bomb. The first successful hydrogen bomb test occurred on November 8, 1957, which had a yield of 1.8 megatons. An amendment to the Atomic Energy Act in 1958 allowed nuclear cooperation once again, and British-U.S. nuclear programs resumed. During the Cold War, British nuclear deterrence came from submarines and nuclear-armed aircraft. The Resolution class ballistic missile submarines armed with the American-built Polaris missile provided the sea deterrent, while aircraft such as the Avro Vulcan, SEPECAT Jaguar, Panavia Tornado and several other Royal Air Force strike aircraft carrying WE.177 gravity bomb provided the air deterrent.
Operation Crossroads
Operation Crossroads was a pair of nuclear weapon tests conducted by the United States at Bikini Atoll in mid-1946. They were the first nuclear weapon tests since Trinity in July 1945, and the first detonations of nuclear devices since the atomic bombing of Nagasaki on August 9, 1945. The purpose of the tests was to investigate the effect of nuclear weapons on warships.
Nuclear weapon
Since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated over two thousand times for testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them. The only countries known to have detonated nuclear weapons—and acknowledge possessing them—are (chronologically by date of first test) the United States, the Soviet Union (succeeded as a nuclear power by Russia), the United Kingdom, France, China, India, Pakistan, and North Korea. Israel is believed to possess nuclear weapons, though, in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states. South Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons.
United States and weapons of mass destruction
The United States is known to have possessed three types of weapons of mass destruction: nuclear weapons, chemical weapons, and biological weapons. The U.S. is the only country to have used nuclear weapons in combat, when it detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki during World War II. It had secretly developed the earliest form of the atomic weapon during the 1940s under the title "Manhattan Project". The United States pioneered the development of both the nuclear fission and hydrogen bombs (the latter involving nuclear fusion). It was the world's first and only nuclear power for four years (1945–1949), until the Soviet Union managed to produce its own nuclear weapon. The United States has the second largest number of deployed nuclear weapons in the world, after Russia.
History of the anti-nuclear movement
In 1945 in the New Mexico desert, American scientists conducted "Trinity," the first nuclear weapons test, marking the beginning of the atomic age. Even before the Trinity test, national leaders debated the impact of nuclear weapons on domestic and foreign policy. Also involved in the debate about nuclear weapons policy was the scientific community, through professional associations such as the Federation of Atomic Scientists and the Pugwash Conference on Science and World Affairs.
Nuclear weapons of the United States
The United States was the first country to manufacture nuclear weapons and is the only country to have used them in combat, with the separate bombings of Hiroshima and Nagasaki in World War II. Before and during the Cold War, it conducted over a thousand nuclear tests and tested many long-range nuclear weapons delivery systems.
History of nuclear weapons
By the time Nazi Germany invaded Poland in 1939, beginning World War II, many of Europe's top scientists had already fled the imminent conflict. Physicists on both sides were well aware of the possibility of utilizing nuclear fission as a weapon, but no one was quite sure how it could be done. 
In August 1939, concerned that Germany might have its own project to develop fission-based weapons, Albert Einstein signed a letter to U.S. President Franklin D. Roosevelt warning him of the threat. Roosevelt responded by setting up the Uranium Committee under Lyman James Briggs but, with little initial funding ($6,000), progress was slow. It was not until the Japanese attack on Pearl Harbor in December, 1941, that the U.S. decided to commit the necessary resources.
History of nuclear weapons
In 1959, a letter in the "Bulletin of the Atomic Scientists" was the start of a successful campaign to stop the Atomic Energy Commission dumping radioactive waste in the sea 19 kilometres from Boston. On November 1, 1961, at the height of the Cold War, about 50,000 women brought together by Women Strike for Peace marched in 60 cities in the United States to demonstrate against nuclear weapons. It was the largest national women's peace protest of the 20th century.
Nuclear history of the United States
The atomic bombings of Hiroshima and Nagasaki (August 1945) heralded the beginning of the Cold War and the prosperity by nuclear of the United States. After the atomic bombings of Hiroshima and Nagasaki, the United States began nuclear weapons tests, Hydrogen bombs were also developed.
Nuclear warfare
Another dimension to the tactical use of nuclear weapons is that of such weapons deployed at sea for use against surface and submarine vessels. Until 1992, vessels of the United States Navy (and their aircraft) deployed various such weapons as bombs, rockets (guided and unguided), torpedoes, and depth charges. Such tactical naval nuclear weapons were considered more acceptable to use early in a conflict because there would be few civilian casualties. It was feared by many planners that such use would probably quickly have escalated into large-scale nuclear war. This situation was particularly exacerbated by the fact that such weapons at sea were not constrained by the safeguards provided by the Permissive Action Link attached to U.S. Air Force and Army nuclear weapons. It is unknown if the navies of the other nuclear powers yet today deploy tactical nuclear weapons at sea.
List of states with nuclear weapons
China tested its first nuclear weapon device ("596") in 1964 at the Lop Nur test site. The weapon was developed as a deterrent against both the United States and the Soviet Union. Two years later, China had a fission bomb capable of being put onto a nuclear missile. It tested its first hydrogen bomb ("Test No. 6") in 1967, a mere 32 months after testing its first nuclear weapon (the shortest fission-to-fusion development known in history). The country is currently thought to have had a stockpile of around 240 warheads, though because of the limited information available, estimates range from 100 to 400. China is the only NPT nuclear-weapon state to give an unqualified negative security assurance with its "no first use" policy. China signed the Nuclear Non-Proliferation Treaty in 1992. On February 25, 2015 U.S. Vice Admiral Joseph Mulloy stated to the House Armed Services Committee's seapower subcommittee that the U.S. does not believe the PLAN currently deploys SLBMs on their submarine fleet.
Nuclear warfare
Nuclear warfare (sometimes atomic warfare or thermonuclear warfare) is a military conflict or political strategy in which nuclear weaponry is used to inflict damage on the enemy. 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 warfare result. A major nuclear exchange would have long-term effects, primarily from the fallout released, and could also lead to a "nuclear winter" that could last for decades, centuries, or even millennia after the initial attack. Some analysts dismiss the nuclear winter hypothesis, and calculate that even with nuclear weapon stockpiles at Cold War highs, although there would be billions of casualties, billions more rural people would nevertheless survive. However, others have argued that secondary effects of a nuclear holocaust, such as nuclear famine and societal collapse, would cause almost every human on Earth to starve to death.
Nuclear weapons testing
The United States conducted six atomic tests before the Soviet Union developed their first atomic bomb (RDS-1) and tested it on August 29, 1949. Neither country had very many atomic weapons to spare at first, and so testing was relatively infrequent (when the U.S. used two weapons for "Operation Crossroads" in 1946, they were detonating over 20% of their current arsenal). However, by the 1950s the United States had established a dedicated test site on its own territory (Nevada Test Site) and was also using a site in the Marshall Islands (Pacific Proving Grounds) for extensive atomic and nuclear testing.
History of nuclear weapons
H. G. Wells was inspired to write about atomic weapons in a 1914 novel, "The World Set Free", which appeared shortly before the First World War.
In a 1924 article, Winston Churchill speculated about the possible military implications: "Might not a bomb no bigger than an orange be found to possess a secret power to destroy a whole block of buildings—nay to concentrate the force of a thousand tons of cordite and blast a township at a stroke?"
Nuclear weapons of the United States
The initial U.S. nuclear program was run by the National Bureau of Standards starting in 1939 under the edict of President Franklin Delano Roosevelt. Its primary purpose was to delegate research and dispense funds. In 1940 the National Defense Research Committee (NDRC) was established, coordinating work under the Committee on Uranium among its other wartime efforts. In June 1941, the Office of Scientific Research and Development (OSRD) was established, with the NDRC as one of its subordinate agencies, which enlarged and renamed the Uranium Committee as the Section on Uranium. In 1941, NDRC research was placed under direct control of Vannevar Bush as the OSRD S-1 Section, which attempted to increase the pace of weapons research. In June 1942, the U.S. Army Corps of Engineers took over the project to develop atomic weapons, while the OSRD retained responsibility for scientific research.
World War III in popular culture
Prescient stories about nuclear war were written before the invention of the atomic bomb. The most notable of these is "The World Set Free", written by H. G. Wells in 1914. During World War II, several nuclear war stories were published in science fiction magazines such as "Astounding". In Robert A. Heinlein's story "Solution Unsatisfactory" the US develops radioactive dust as the ultimate weapon of war and uses it to destroy Berlin in 1945 and end the war with Germany. The Soviet Union then develops the same weapon independently, and war between it and the US follows. The bombing of Hiroshima and Nagasaki in 1945 made stories of a future global nuclear war look less like fiction and more like prophecy. When William Faulkner received the Nobel Prize in Literature in 1949, he spoke about Cold War themes in art. He worried that younger writers were too preoccupied with the question of "When will I be blown up?"
Atomic bombings of Hiroshima and Nagasaki
The American monopoly on nuclear weapons lasted only four years before the Soviet Union detonated an atomic bomb in September 1949. The United States responded with the development of the hydrogen bomb, a nuclear weapon a thousand times as powerful as the bombs that devastated Hiroshima and Nagasaki. Such ordinary fission bombs would henceforth be regarded as small tactical nuclear weapons. By 1986, the United States would have 23,317 nuclear weapons, while the Soviet Union had 40,159. By 2017, nine nations had nuclear weapons, but Japan was not one of them. Japan reluctantly signed the Treaty on the Non-Proliferation of Nuclear Weapons in February 1970, but it still sheltered under the American nuclear umbrella. American nuclear weapons were stored on Okinawa, and sometimes in Japan itself, albeit in contravention of agreements between the two nations. Lacking the resources to fight the Soviet Union using conventional forces, the Western Alliance came to depend on the use of nuclear weapons to defend itself during the Cold War, a policy that became known in the 1950s as the New Look. In the decades after Hiroshima and Nagasaki, the United States would threaten to use its nuclear weapons many times.
Nuclear technology
Ultimately, the Manhattan Project manufactured nuclear weapons based on each of these elements. They detonated the first nuclear weapon in a test code-named "Trinity", near Alamogordo, New Mexico, on July 16, 1945. The test was conducted to ensure that the implosion method of detonation would work, which it did. A uranium bomb, Little Boy, was dropped on the Japanese city Hiroshima on August 6, 1945, followed three days later by the plutonium-based Fat Man on Nagasaki. In the wake of unprecedented devastation and casualties from a single weapon, the Japanese government soon surrendered, ending World War II.
Uranium
As little as 15 lb (7 kg) of uranium-235 can be used to make an atomic bomb. The first nuclear bomb used in war, "Little Boy", relied on uranium fission, but the very first nuclear explosive (the "Gadget" used at Trinity) and the bomb that destroyed Nagasaki ("Fat Man") were both plutonium bombs.
Carl von Clausewitz
The deterrence strategy of the United States in the 1950s was closely inspired by President Dwight Eisenhower’s reading of Clausewitz as a young officer in the 1920s. Eisenhower was greatly impressed by Clausewitz’s example of a theoretical, idealised “absolute war” in "Vom Krieg" as a way of demonstrating how absurd it would be to attempt such a strategy in practice. For Eisenhower, the age of nuclear weapons had made what was for Clausewitz in the early 19th century only a theoretical vision an all too real possibility in the mid-20th century. From Eisenhower's viewpoint, the best deterrent to war was to show the world just how appalling and horrific a nuclear “absolute war” would be if it should ever occur, hence a series of much publicised nuclear tests in the Pacific, giving first priority in the defence budget to nuclear weapons and delivery systems over conventional weapons, and making repeated statements in public that the United States was able and willing at all times to use nuclear weapons. In this way through the massive retaliation doctrine and the closely related foreign policy concept of brinkmanship, Eisenhower hoped to hold out a creditable vision of Clausewitzian nuclear “absolute war” in order to deter the Soviet Union and/or China from ever risking a war or even conditions that might lead to a war with the United States.
After 1970, some theorists claimed that nuclear proliferation made Clausewitzian concepts obsolete after the 20th-century period in which they dominated the world. John E. Sheppard, Jr., argues that by developing nuclear weapons, state-based conventional armies simultaneously both perfected their original purpose, to destroy a mirror image of themselves, and made themselves obsolete. No two powers have used nuclear weapons against each other, instead using conventional means or proxy wars to settle disputes. If such a conflict did occur, presumably both combatants would be annihilated. Heavily influenced by the war in Vietnam and by antipathy to American strategist Henry Kissinger, the American biologist, musician, and game-theorist Anatol Rapoport argued in 1968 that a Clausewitzian view of war was not only obsolete in the age of nuclear weapons, but also highly dangerous as it promoted a "zero-sum paradigm" to international relations and a "dissolution of rationality" amongst decision-makers.
Atomic bombings of Hiroshima and Nagasaki
During the final stage of World War II, the United States detonated two nuclear weapons over the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945, respectively. The United States dropped the bombs after obtaining the consent of the United Kingdom, as required by the Quebec Agreement. The two bombings killed 129,000–226,000 people, most of whom were civilians. They remain the only use of nuclear weapons in the history of armed conflict.
Nuclear arms race
France became the fourth nation to possess nuclear weapons on February 13, 1960, when the atomic bomb "Gerboise Bleue" was detonated in Algeria, then still a French colony [Formally a part of the Metropolitan France.] France began making plans for a nuclear-weapons program shortly after the Second World War, but the program did not actually begin until the late 1950s. Eight years later, France conducted its first thermonuclear test above Fangatuafa Atoll. It had a yield of 2.6 megatons. This bomb significantly contaminated the atoll with radiation for six years, making it off-limits to humans. During the Cold War, the French nuclear deterrent was centered around the Force de frappe, a nuclear triad consisting of Dassault Mirage IV bombers carrying such nuclear weapons as the AN-22 gravity bomb and the ASMP stand-off attack missile, Pluton and Hades ballistic missiles, and the Redoutable class submarine armed with strategic nuclear missiles.
Weapons in science fiction
Nuclear weapons are a staple element in science fiction novels. The phrase "atomic bomb" predates their existence, and dates back to H. G. Wells' "The World Set Free" (1914) when scientists had discovered that radioactive decay implied potentially limitless energy locked inside of atomic particles (Wells' atomic bombs were only as powerful as conventional explosives, but would continue exploding for days on end). Cleve Cartmill predicted a chain-reaction-type nuclear bomb in his 1944 science-fiction story "Deadline", which led to the FBI investigating him, due to concern over a potential breach of security on the Manhattan Project.
Nuclear Holocausts: Atomic War in Fiction
Nuclear Holocausts: Atomic War in Fiction, 1895–1984 was written by Paul Brians and published in 1987. This comprehensive study covers nuclear holocaust fiction published in English-language works between 1895 and 1984. Brians notes that 1895 marked the first appearance of an atomic weapon in fiction: Robert Cromie's "Crack of Doom". The latter date marks the conclusion of this study's time span.
Duck and cover
The United States' monopoly on nuclear weapons was broken by the Soviet Union in 1949 when it tested its first nuclear explosive, the RDS-1. With this, many in the US Government, as well as many citizens, perceived that the United States was more vulnerable than it had ever been before. In 1950, during the first big Civil Defense push of the Cold War—and coinciding with the "Alert America!" initiative to educate Americans on nuclear preparedness, the adult-orientated Survival Under Atomic Attack was published. It contains "duck and cover" or more accurately, cover and then duck advice without using those specific terms in its "Six Survival Secrets For Atomic Attacks" section. "1. Try to Get Shielded 2. Drop Flat on Ground or Floor 3. Bury Your Face in Your Arms ("crook of your elbow")". The child-oriented film "Duck and Cover" was produced a year later by the Federal Civil Defense Administration in 1951.
Nuclear War (disambiguation)
A Nuclear War is a war in which nuclear weapons are used.
Pacific War
On 6 August 1945, the US dropped an atomic bomb on the Japanese city of Hiroshima in the first nuclear attack in history. In a press release issued after the atomic bombing of Hiroshima, Truman warned Japan to surrender or "...expect a rain of ruin from the air, the like of which has never been seen on this earth." Three days later, on 9 August, the US dropped another atomic bomb on Nagasaki, the last nuclear attack in history. More than 140,000–240,000 people died as a direct result of these two bombings. The necessity of the atomic bombings has long been debated, with detractors claiming that a naval blockade and aerial bombing campaign had already made invasion, hence the atomic bomb, unnecessary. However, other scholars have argued that the bombings shocked the Japanese government into surrender, with the Emperor finally indicating his wish to stop the war. Another argument in favor of the atomic bombs is that they helped avoid Operation Downfall, or a prolonged blockade and bombing campaign, any of which would have exacted much higher casualties among Japanese civilians. Historian Richard B. Frank wrote that a Soviet invasion of Japan was never likely because they had insufficient naval capability to mount an amphibious invasion of Hokkaidō.
History of weapons
Chemical weapons were first used on a large scale on the battlefield in World War I, starting from 1914, despite existing international conventions that prohibited the use of such weapons.
Nuclear weapons debate
Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. Some—notably a number at the University of Chicago Metallurgical Laboratory, represented in part by Leó Szilárd—lobbied early on that the atomic bomb should only be built as a deterrent against Nazi Germany getting a bomb, and should not be used against populated cities. The Franck Report argued in June 1945 that instead of being used against a city, the first atomic bomb should be "demonstrated" to the Japanese on an uninhabited area. This recommendation was not agreed with by the military commanders, the Los Alamos Target Committee (made up of other scientists), or the politicians who had input into the use of the weapon. Because the Manhattan Project was considered to be "top secret", there was no public discussion of the use of nuclear arms, and even within the U.S. government, knowledge of the bomb was extremely limited.
History of nuclear weapons
Strategic weapons—weapons that could threaten an entire country—relied, for the time being, on long-range bombers that could penetrate deep into enemy territory. In the U.S., this requirement led, in 1946, to creation of the Strategic Air Command—a system of bombers headed by General Curtis LeMay (who previously presided over the firebombing of Japan during WWII). In operations like Chrome Dome, SAC kept nuclear-armed planes in the air 24 hours a day, ready for an order to attack Moscow.
Nuclear weapons and the United Kingdom
Believing that the United Kingdom was extremely vulnerable to a nuclear attack to which defence was impossible, the Chiefs of Staff and the RAF first advocated a British nuclear deterrence—not just nuclear weapons—in 1945: "It is our opinion that our only chance of securing a quick decision is by launching a devastating attack upon [enemy cities] with absolute weapons." In 1947 the Chiefs of Staff stated that even with American help the United Kingdom could not prevent the "vastly superior" Soviet forces from overrunning Western Europe, from which Russia could destroy Britain with missiles without using atomic weapons. Only "the threat of large-scale damage from similar weapons" could prevent the Soviet Union from using atomic weapons in a war.
Nagasaki
Less than a second after the detonation, the north of the city was destroyed and 35,000 people were killed. Among the deaths were 6,200 out of the 7,500 employees of the Mitsubishi Munitions plant, and 24,000 others (including 2,000 Koreans) who worked in other war plants and factories in the city, as well as 150 Japanese soldiers. The industrial damage in Nagasaki was high, leaving 68–80% of the non-dock industrial production destroyed. It was the second and, to date, the last use of a nuclear weapon in combat, and also the second detonation of a plutonium bomb. The first combat use of a nuclear weapon was the "Little Boy" bomb, which was dropped on the Japanese city of Hiroshima on August 6, 1945. The first plutonium bomb was tested in central New Mexico, United States, on July 16, 1945. The Fat Man bomb was somewhat more powerful than the one dropped over Hiroshima, but because of Nagasaki's more uneven terrain, there was less damage.
Military history
In the 10th century, the invention of gunpowder led to many new weapons that were improved over time. Black powder was used in China since the 4th century, but it was not used as a weapon until the 11th century. Until the mid-15th century, guns were held in one hand, while the explosive charge was ignited by the other hand. Then came the matchlock, which was used widely until around the 1720s. Leonardo da Vinci made drawings of the wheel lock which made its own sparks. Eventually, the matchlock was replaced by the flintlock. Cannons were first used in Europe in the early 14th century, and played a vital role in the Hundred Years' War. The first cannons were simply welded metal bars in the form of a cylinder, and the first cannonballs were made of stone. By 1346, at the Battle of Crécy, the cannon had been used; at the Battle of Agincourt they would be used again.
Nuclear warfare
Pakistan's nuclear policy was significantly affected by the 1965 war with India. The 1971 war and India's nuclear program played a role in Pakistan's decision to go nuclear. India and Pakistan both decided not to participate in the NPT. Pakistan's nuclear policy became fixated on India because India refused to join the NPT and remain opened to nuclear weapons. Impetus by Indian actions spurred Pakistan's nuclear research. After nuclear weapons construction was started by Bhutto's command, the chair of Pakistan Atomic Energy Commission Usmani quit in objection. The 1999 war between Pakistan and India occurred after both acquired nuclear weapons. It is believed by some that nuclear weapons are the reason a big war has not broken out in the subcontinent. India and Pakistan still have a risk of nuclear conflict on the issue of war over Kashmir. Nuclear capability deliverable by sea were claimed by Pakistan in 2012. The aim was to achieve a "minimum credible deterrence". Pakistan's nuclear program culminated in the tests at Chagai. One of the aims of Pakistan's programs is fending off potential annexation and maintaining independence.
Uranium
Two major types of atomic bombs were developed by the United States during World War II: a uranium-based device (codenamed "Little Boy") whose fissile material was highly enriched uranium, and a plutonium-based device (see Trinity test and "Fat Man") whose plutonium was derived from uranium-238. The uranium-based Little Boy device became the first nuclear weapon used in war when it was detonated over the Japanese city of Hiroshima on 6 August 1945. Exploding with a yield equivalent to 12,500 tonnes of TNT, the blast and thermal wave of the bomb destroyed nearly 50,000 buildings and killed approximately 75,000 people (see Atomic bombings of Hiroshima and Nagasaki). Initially it was believed that uranium was relatively rare, and that nuclear proliferation could be avoided by simply buying up all known uranium stocks, but within a decade large deposits of it were discovered in many places around the world.
No first use
China became the first nation to propose and pledge NFU policy when it first gained nuclear capabilities in 1964, stating "not to be the first to use nuclear weapons at any time or under any circumstances". During the Cold War, China decided to keep the size of its nuclear arsenal small rather than compete in an international arms race with the United States and the Soviet Union. China has repeatedly re-affirmed its no-first-use policy in recent years, doing so in 2005, 2008, 2009 and again in 2011. China has also consistently called on the United States to adopt a no-first-use policy, to reach an NFU agreement bilaterally with China, and to conclude an NFU agreement among the five nuclear weapon states. The United States has repeatedly refused these calls.
Nuclear weapons testing
The first atomic weapons test was conducted near Alamogordo, New Mexico, on July 16, 1945, during the Manhattan Project, and given the codename "Trinity". The test was originally to confirm that the implosion-type nuclear weapon design was feasible, and to give an idea of what the actual size and effects of a nuclear explosion would be before they were used in combat against Japan. While the test gave a good approximation of many of the explosion's effects, it did not give an appreciable understanding of nuclear fallout, which was not well understood by the project scientists until well after the atomic bombings of Hiroshima and Nagasaki.
History of nuclear weapons
The collapse of the Soviet Union in 1991 essentially ended the Cold War. However, the end of the Cold War failed to end the threat of nuclear weapon use, although global fears of nuclear war reduced substantially. In a major move of symbolic de-escalation, Boris Yeltsin, on January 26, 1992, announced that Russia planned to stop targeting United States cities with nuclear weapons.
History of nuclear weapons
National leaders debated the impact of nuclear weapons on domestic and foreign policy. Also involved in the debate about nuclear weapons policy was the scientific community, through professional associations such as the Federation of Atomic Scientists and the Pugwash Conference on Science and World Affairs. Radioactive fallout from nuclear weapons testing was first drawn to public attention in 1954 when a Hydrogen bomb test in the Pacific contaminated the crew of the Japanese fishing boat "Lucky Dragon". One of the fishermen died in Japan seven months later. The incident caused widespread concern around the world and "provided a decisive impetus for the emergence of the anti-nuclear weapons movement in many countries". The anti-nuclear weapons movement grew rapidly because for many people the atomic bomb "encapsulated the very worst direction in which society was moving".
Nuclear warfare
Either a limited or full-scale nuclear exchange could occur during an "accidental nuclear war", in which the use of nuclear weapons is triggered unintentionally. Postulated triggers for this scenario have included malfunctioning early warning devices and/or targeting computers, deliberate malfeasance by rogue military commanders, consequences of an accidental straying of warplanes into enemy airspace, reactions to unannounced missile tests during tense diplomatic periods, reactions to military exercises, mistranslated or miscommunicated messages, and others. A number of these scenarios actually occurred during the Cold War, though none resulted in the use of nuclear weapons. Many such scenarios have been depicted in popular culture, such as in the 1959 film "On the Beach", the 1962 novel "Fail-Safe" (released as a film in 1964); the film "WarGames", released in 1983; and the film "", also released in 1964.
Nuclear warfare
On August 29, 1949, the Soviet Union tested its first nuclear weapon at Semipalatinsk in Kazakhstan (see also Soviet atomic bomb project). Scientists in the United States from the Manhattan Project had warned that, in time, the Soviet Union would certainly develop nuclear capabilities of its own. Nevertheless, the effect upon military thinking and planning in the United States was dramatic, primarily because American military strategists had not anticipated the Soviets would "catch up" so soon. However, at this time, they had not discovered that the Soviets had conducted significant nuclear espionage of the project from spies at Los Alamos, the most significant of which was done by the theoretical physicist Klaus Fuchs. The first Soviet bomb was more or less a deliberate copy of the Fat Man plutonium device. In the same year the first US-Soviet nuclear war plan was penned in the US with Operation Dropshot.
Nuclear weapons of the United States
The United States first began developing nuclear weapons during World War II under the order of President Franklin Roosevelt in 1939, motivated by the fear that they were engaged in a race with Nazi Germany to develop such a weapon. After a slow start under the direction of the National Bureau of Standards, at the urging of British scientists and American administrators, the program was put under the Office of Scientific Research and Development, and in 1942 it was officially transferred under the auspices of the United States Army and became known as the Manhattan Project, an American, British and Canadian joint venture. Under the direction of General Leslie Groves, over thirty different sites were constructed for the research, production, and testing of components related to bomb-making. These included the Los Alamos National Laboratory at Los Alamos, New Mexico, under the direction of physicist Robert Oppenheimer, the Hanford plutonium production facility in Washington, and the Y-12 National Security Complex in Tennessee.
Nuclear power
The U.S. Army, nuclear power program, formally commenced in 1954. Under its management, the 2 megawatt SM-1, at Fort Belvoir, Virginia, was the first in the United States to supply electricity in an industrial capacity to the commercial grid (VEPCO), in April 1957.
Chemical weapons in World War I
Chemical weapons have been used in at least a dozen wars since the end of the First World War; they were not used in combat on a large scale until Iraq used mustard gas and the more deadly nerve agents in the Halabja chemical attack near the end of the 8-year Iran–Iraq War. The full conflict's use of such weaponry killed around 20,000 Iranian troops (and injured another 80,000), around a quarter of the number of deaths caused by chemical weapons during the First World War.
National technical means of verification
France tested its first nuclear weapon on February 13, 1960 in Algeria. This came as no surprise, as multiple US intelligence sources and methods had been following the program since France began considering nuclear weapons in 1946.
History of nuclear weapons
In 1956, France formed a secret Committee for the Military Applications of Atomic Energy and a development program for delivery vehicles. With the return of Charles de Gaulle to the French presidency in 1958, final decisions to build a bomb were made, which led to a successful test in 1960. Since then, France has developed and maintained its own nuclear deterrent independent of NATO.
India and weapons of mass destruction
India's nuclear programme can trace its origins to March 1944 and its three-stage efforts in technology were established by Homi Jehangir Bhabha when he founded the nuclear research centre, the Tata Institute of Fundamental Research. India's loss of territory to China in a brief Himalayan border war in October 1962, provided the New Delhi government impetus for developing nuclear weapons as a means of deterring potential Chinese aggression. India first tested a nuclear device in 1974 (code-named "Smiling Buddha"), under Prime Minister Indira Gandhi, which it called a "peaceful nuclear explosion." The test used plutonium produced in the Canadian-supplied CIRUS reactor, and raised concerns that nuclear technology supplied for peaceful purposes could be diverted to weapons purposes. This also stimulated the early work of the Nuclear Suppliers Group. India performed further nuclear tests in 1998 (code-named "Operation Shakti"). In 1998, as a response to the continuing tests, the United States and Japan imposed sanctions on India, which have since been lifted.
List of states with nuclear weapons
France tested its first nuclear weapon in 1960 ("Gerboise Bleue"), based mostly on its own research. It was motivated by the Suez Crisis diplomatic tension "vis-à-vis" both the Soviet Union and the Free World allies United States and United Kingdom. It was also relevant to retain great power status, alongside the United Kingdom, during the post-colonial Cold War (see: Force de frappe). France tested its first hydrogen bomb in 1968 ("Opération Canopus"). After the Cold War, France has disarmed 175 warheads with the reduction and modernization of its arsenal that has now evolved to a dual system based on submarine-launched ballistic missiles (SLBMs) and medium-range air-to-surface missiles (Rafale fighter-bombers). However new nuclear weapons are in development and reformed nuclear squadrons were trained during Enduring Freedom operations in Afghanistan. France signed the Nuclear Non-Proliferation Treaty in 1992. In January 2006, President Jacques Chirac stated a terrorist act or the use of weapons of mass destruction against France would result in a nuclear counterattack. In February 2015, President Francois Hollande stressed the need for a nuclear deterrent in "a dangerous world". He also detailed the French deterrent as "less than 300" nuclear warheads, three sets of 16 submarine-launched ballistic missiles and 54 medium-range air-to-surface missiles" and urged other states to show similar transparency.
Nuclear technology
Since these bombings, no nuclear weapons have been deployed offensively. Nevertheless, they prompted an arms race to develop increasingly destructive bombs to provide a nuclear deterrent. Just over four years later, on August 29, 1949, the Soviet Union detonated its first fission weapon. The United Kingdom followed on October 2, 1952; France, on February 13, 1960; and China component to a nuclear weapon. Approximately half of the deaths from Hiroshima and Nagasaki died two to five years afterward from radiation exposure. A radiological weapons is a type of nuclear weapon designed to distribute hazardous nuclear material in enemy areas. Such a weapon would not have the explosive capability of a fission or fusion bomb, but would kill many people and contaminate a large area. A radiological weapon has never been deployed. While considered useless by a conventional military, such a weapon raises concerns over nuclear terrorism.
List of states with nuclear weapons
The following is a list of states that have admitted the possession of nuclear weapons or are presumed to possess them, the approximate number of warheads under their control, and the year they tested their first weapon and their force configuration. This list is informally known in global politics as the "Nuclear Club". With the exception of Russia and the United States (which have subjected their nuclear forces to independent verification under various treaties) these figures are estimates, in some cases quite unreliable estimates. In particular, under the Strategic Offensive Reductions Treaty thousands of Russian and U.S. nuclear warheads are inactive in stockpiles awaiting processing. The fissile material contained in the warheads can then be recycled for use in nuclear reactors.
Nuclear fission
One class of nuclear weapon, a "fission bomb" (not to be confused with the "fusion bomb"), otherwise known as an "atomic bomb" or "atom bomb", is a fission reactor designed to liberate as much energy as possible as rapidly as possible, before the released energy causes the reactor to explode (and the chain reaction to stop). Development of nuclear weapons was the motivation behind early research into nuclear fission which the Manhattan Project during World War II (September 1, 1939 – September 2, 1945) carried out most of the early scientific work on fission chain reactions, culminating in the three events involving fission bombs that occurred during the war. The first fission bomb, codenamed "The Gadget", was detonated during the Trinity Test in the desert of New Mexico on July 16, 1945. Two other fission bombs, codenamed "Little Boy" and "Fat Man", were used in combat against the Japanese cities of Hiroshima and Nagasaki in on August 6 and 9, 1945 respectively.
Nuclear weapons in popular culture
Pictures of nuclear weapons themselves (the actual casings) were not made public until 1960, and even those were only mock-ups of the "Fat Man" and "Little Boy" weapons dropped on Japan—not the more powerful weapons developed more recently. Diagrams of the general principles of operation of thermonuclear weapons have been available in very general terms since at least 1969 in at least two encyclopedia articles, and open literature research into inertial confinement fusion has been at least richly suggestive of how the "secondary" and "inter" stages of thermonuclear weapons work.
Manhattan Project
The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the U.S. Army Corps of Engineers. Nuclear physicist Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the actual bombs. The Army component of the project was designated the Manhattan District; "Manhattan" gradually superseded the official codename, Development of Substitute Materials, for the entire project. Along the way, the project absorbed its earlier British counterpart, Tube Alloys. The Manhattan Project began modestly in 1939, but grew to employ more than 130,000 people and cost nearly US$2 billion (about $ in dollars). Over 90% of the cost was for building factories and to produce fissile material, with less than 10% for development and production of the weapons. Research and production took place at more than 30 sites across the United States, the United Kingdom, and Canada.
Nuclear warfare
During the final stages of World War II in 1945, the United States conducted atomic raids on the Japanese cities of Hiroshima and Nagasaki, the first on August 6, 1945, and the second on August 9, 1945. These two events were the only times nuclear weapons have been used in combat.
Nuclear artillery
After the abortive effort with purpose-built artillery pieces, the Soviet approach to nuclear artillery was that nuclear munitions should be fired by standard guns and howitzers (without modification), in normal artillery units. The first nuclear weapon for use from standard 152 mm artillery, called ZBV3, was finally accepted in 1965. Subsequent weapon designs followed using existing and new technology:
Nuclear weapons of the United States
This was the beginning of the Manhattan Project, run as the Manhattan Engineering District (MED), an agency under military control that was in charge of developing the first atomic weapons. After World War II, the MED maintained control over the U.S. arsenal and production facilities and coordinated the Operation Crossroads tests. In 1946 after a long and protracted debate, the Atomic Energy Act of 1946 was passed, creating the Atomic Energy Commission (AEC) as a civilian agency that would be in charge of the production of nuclear weapons and research facilities, funded through Congress, with oversight provided by the Joint Committee on Atomic Energy. The AEC was given vast powers of control over secrecy, research, and money, and could seize lands with suspected uranium deposits. Along with its duties towards the production and regulation of nuclear weapons, it was also in charge of stimulating development and regulating civilian nuclear power. The full transference of activities was finalized in January 1947.
History of nuclear weapons
In 1946 Congress established the civilian Atomic Energy Commission (AEC) to take over the development of nuclear weapons from the military, and to develop nuclear power. The AEC made use of many private companies in processing uranium and thorium and in other urgent tasks related to the development of bombs. Many of these companies had very lax safety measures and employees were sometimes exposed to radiation levels far above what was allowed then or now. In 1974, the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the Army Corps of Engineers was set up to deal with contaminated sites left over from these operations.
Nuclear espionage
During the Manhattan Project, the joint effort during World War II by the United States, the United Kingdom, and Canada to create the first nuclear weapons, there were many instances of nuclear espionage in which project scientists or technicians channeled information about bomb development and design to the Soviet Union. These people are often referred to as the Atomic Spies, and their work continued into the early Cold War. Because most of these cases became well known in the context of the anti-Communist 1950s, there has been long-standing dispute over the exact details of these cases, though some of this was settled with the making public of the Venona project transcripts, which were intercepted and decrypted messages between Soviet agents and the Soviet government. Some issues remain unsettled, however.
History of nuclear weapons
In December 1938, Otto Hahn and Fritz Strassmann sent a manuscript to "Naturwissenschaften" reporting that they had detected the element barium after bombarding uranium with neutrons. Lise Meitner and her nephew Otto Robert Frisch correctly interpreted these results as being due to the splitting of the uranium atom. (Frisch confirmed this experimentally on January 13, 1939.) They gave the process the name "fission" because of its similarity to the splitting of a cell into two new cells.
Even before it was published, news of Meitner’s and Frisch’s interpretation crossed the Atlantic.
Scientists at Columbia University decided to replicate the experiment and on January 25, 1939, conducted the first nuclear fission experiment in the United States in the basement of Pupin Hall. The following year, they identified the active component of uranium as being the rare isotope uranium-235.
International Court of Justice advisory opinion on the Legality of the Threat or Use of Nuclear Weapons
Ultimately, the court was unable to find an "opinio juris" (that is, legal consensus) that nuclear weapons are illegal to possess. (paragraph 65) However, in practice, nuclear weapons have not been used in war since 1945 and there have been numerous UN resolutions condemning their use (however, such resolutions are not universally supported—most notably, the nuclear powers object to them).(paragraph 68–73) The ICJ did not find that these facts demonstrated a new and clear customary law absolutely forbidding nuclear weapons.
Nuclear power
In the United States, where Fermi and Szilárd had both emigrated, the discovery of the nuclear chain reaction led to the creation of the first man-made reactor, the research reactor known as Chicago Pile-1, which achieved self-sustaining power/criticality on December 2, 1942. The reactor's development was part of the Manhattan Project, the Allied effort to create atomic bombs during World War II. It led to the building of larger single-purpose production reactors, such as the X-10 Pile, for the production of weapons-grade plutonium for use in the first nuclear weapons. The United States tested the first nuclear weapon in July 1945, the Trinity test, with the atomic bombings of Hiroshima and Nagasaki taking place one month later.
Atomic Energy Act of 1946
Nuclear weapons were developed during World War II by the wartime Manhattan Project. Key scientists working on the project anticipated that their development would have wide-ranging implications. However the project director, Major General Leslie R. Groves Jr., was reluctant to spend project funds on activities beyond those required to win the war. Nonetheless, Arthur Compton of the Metallurgical Project in Chicago commissioned a report on post-war nuclear energy, and the Military Policy Committee, the Manhattan Project's governing body, commissioned a similar study by Richard Tolman. Both reports called for a comprehensive, government-supported nuclear energy program, with military, scientific, and industrial aspects.
Nuclear history of the United States
Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. The role of the two atomic bombings of the country in Japan's surrender and the U.S.'s ethical justification for them has been the subject of scholarly and popular debate for decades. The question of whether nations should have nuclear weapons, or test them, has been continually and nearly universally controversial.
History of nuclear weapons
After the collapse of Eastern Military High Command and the disintegration of Pakistan as a result of the 1971 Winter war, Bhutto of Pakistan launched scientific research on nuclear weapons. The Indian test caused Pakistan to spur its programme, and the ISI conducted successful espionage operations in the Netherlands, while also developing the programme indigenously. India tested fission and perhaps fusion devices in 1998, and Pakistan successfully tested fission devices that same year, raising concerns that they would use nuclear weapons on each other.
2010 NPT Review Conference
The Nuclear Nonproliferation Treaty (NPT), which entered into force in 1970, recognizes five countries as nuclear-weapon states (the United States, Russia, the United Kingdom, France, and China), who commit to pursue disarmament, and the right of other signatories to use nuclear technology for peaceful purposes, conditional upon their non-acquisition of nuclear weapons. Its ratification is nearly universal because it is adhered by 189 states, including five nuclear-weapon states, with the exception of Israel, India, and Pakistan. North Korea left the NPT and tested its first nuclear weapon in 2006.
Nuclear weapons and the United Kingdom
By 1949, international control of atomic weapons seemed almost impossible to achieve, and Truman proposed to the Joint Committee on Atomic Energy in July a "full partnership" with Britain in exchange for uranium; negotiations between the two countries began that month. While the first Soviet atomic bomb test in August 1949 was embarrassing to the British (who had not expected a Soviet atomic weapon until 1954) for having been beaten, it was for the Americans another reason for cooperation. Although they would soon have their own nuclear capability, the British proposed that instead of building their own uranium-enrichment plant they would send most of their scientists to work in the US, and swap plutonium from Windscale for enriched uranium from the US. While Britain would not formally give up building or researching its own weapons, the US would manufacture all the bombs and allocate some to Britain.
Nuclear weapons testing
The first nuclear device was detonated as a test by the United States at the Trinity site on July 16, 1945, with a yield approximately equivalent to 20 kilotons of TNT. The first thermonuclear weapon technology test of engineer device, codenamed "Ivy Mike", was tested at the Enewetak Atoll in the Marshall Islands on November 1, 1952 (local date), also by the United States. The largest nuclear weapon ever tested was the "Tsar Bomba" of the Soviet Union at Novaya Zemlya on October 30, 1961, with the largest yield ever seen, an estimated 50–58 megatons.
Nuclear weapons of the United States
In the early 1980s, the revival of the nuclear arms race triggered large protests about nuclear weapons. On June 12, 1982, one million people demonstrated in New York City's Central Park against nuclear weapons and for an end to the cold war arms race. It was the largest anti-nuclear protest and the largest political demonstration in American history. International Day of Nuclear Disarmament protests were held on June 20, 1983 at 50 sites across the United States. There were many Nevada Desert Experience protests and peace camps at the Nevada Test Site during the 1980s and 1990s.
Military history of Jewish Americans
America's rise as a nuclear power resulted directly from the Manhattan Project, codename for a project during World War II to develop the first atomic bombs for wartime use. The project's roots began in 1939 when, at the urging of Leó Szilárd, Albert Einstein signed the Einstein–Szilárd letter to US president Franklin D. Roosevelt expressing his concerns that Nazi Germany may be trying to develop nuclear weapons.
Nuclear weapons testing
The early tests were used primarily to discern the military effects of atomic weapons ("Crossroads" had involved the effect of atomic weapons on a navy, and how they functioned underwater) and to test new weapon designs. During the 1950s, these included new hydrogen bomb designs, which were tested in the Pacific, and also new and improved fission weapon designs. The Soviet Union also began testing on a limited scale, primarily in Kazakhstan. During the later phases of the Cold War, though, both countries developed accelerated testing programs, testing many hundreds of bombs over the last half of the 20th century.
Nuclear warfare
Recent studies undertaken by the CIA cite the enduring India-Pakistan conflict as the one "flash point" most likely to escalate into a nuclear war. During the Kargil War in 1999, Pakistan came close to using its nuclear weapons in case the conventional military situation underwent further deterioration. Pakistan's foreign minister had even warned that it would "use any weapon in our arsenal", hinting at a nuclear strike against India. The statement was condemned by the international community, with Pakistan denying it later on. This conflict remains the only war (of any sort) between two declared nuclear powers. The 2001-2002 India-Pakistan standoff again stoked fears of nuclear war between the two countries. Despite these very serious and relatively recent threats, relations between India and Pakistan have been improving somewhat over the last few years. However, with the November 26, 2008 Mumbai terror attacks, tensions again worsened.
History of nuclear weapons
After World War II, the balance of power between the Eastern and Western blocs and the fear of global destruction prevented the further military use of atomic bombs. This fear was even a central part of Cold War strategy, referred to as the doctrine of Mutually Assured Destruction. So important was this balance to international political stability that a treaty, the Anti-Ballistic Missile Treaty (or ABM treaty), was signed by the U.S. and the USSR in 1972 to curtail the development of defenses against nuclear weapons and the ballistic missiles that carry them. This doctrine resulted in a large increase in the number of nuclear weapons, as each side sought to ensure it possessed the firepower to destroy the opposition in all possible scenarios.
Nuclear warfare
In 1960, the United States developed its first Single Integrated Operational Plan, a range of targeting options, and described launch procedures and target sets against which nuclear weapons would be launched, variants of which were in use from 1961 to 2003. That year also saw the start of the Missile Defense Alarm System, an American system of 12 early-warning satellites that provided limited notice of Soviet intercontinental ballistic missile launches between 1960 and 1966. The Ballistic Missile Early Warning System was completed in 1964.