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Diplomacy and Conflict • The Arms Race
Overview

Nuclear weapons are the deadliest of bombs, designed to explode due to nuclear fission or fusion. The use of nuclear weapons to end World War II in 1945 forever changed how the public would look at nuclear energy. For much of the Cold War era, Americans lived in fear of a nuclear war that would destroy the world. Created by either breaking up heavy atoms like uranium into lighter atoms (fission) or joining such light atoms as hydrogen into heavier atoms (fusion), nuclear energy was unique to the last half of the 20th century. When harnessed correctly, it can produce major changes in electric power generation, medicine, and warfare. Public fear over the use of nuclear weapons, however, has often stymied nuclear energy's more positive pursuits.

Creating Nuclear Energy

The creation of nuclear energy is based on a few complex concepts. Atoms are the smallest subdivision of matter that have identifiable physical and chemical properties. However, atoms are actually composed of a nucleus, which itself is made of protons and neutrons and an outer shell containing electrons. Nuclear energy originates from processes involving the protons and neutrons in the nucleus, while physical and chemical processes originate from the electrons in the outer shell.

An element is a material that is made of only one kind of atom, meaning all have the same number of protons in their nucleus. However, the number of neutrons in the atom may vary, creating isotopes of the element that are identical chemically but act differently in nuclear processes. An example is hydrogen, which always has one proton, but it can have from zero to two neutrons, each variant being a different isotope.

Multiple isotopes exist for every element but not all are stable, meaning that some change to another isotope over time. Some isotopes will discard neutrons, becoming a lighter isotope of the same element in a process called radioactive decay, while other isotopes, usually very heavy ones, will discard large numbers of protons and neutrons, becoming isotopes of a lighter element in a process called fission. Some isotopes, usually very light ones, will combine under extremely high temperatures to form heavier isotopes of other elements in a process called fusion. All nuclear processes release radiation while the isotopes are changing, which can be very harmful to living organisms.

Creating a Bomb

Early in the 20th century, scientists demonstrated that the nucleus of an atom could decay in some circumstances, which accounted for the radiation emanating from such naturally radioactive materials as radium and uranium. They also showed that the radiation came from individual nuclei that shed protons and neutrons, becoming a different isotope.

During the same time, physicist Albert Einstein proposed a complex theory about space and time that included the formula Energy = Mass X Speed of Light Squared (E=MC2), which showed quantitatively how much energy would be released from each kind of decay. A worldwide effort to understand nuclear processes and to harness the released energy led in 1934 to the discovery that splitting an atom of uranium with a neutron caused the atom to fission, releasing large amounts of energy and two more neutrons to fission other uranium atoms in a process called a chain reaction. The discovery triggered several projects to develop practical uses of the released energy, mostly for bombs.

The Manhattan Project

By 1942, with World War II under way and widespread U.S. fears that Germany would develop nuclear weapons first and change the course of the war, a consortium of scientists encouraged the American government to launch a major program to develop a new type of bomb based on the fission process, called an atomic bomb. The resulting effort, known as the Manhattan Project and led by physicist J. Robert Oppenheimer, was given high priority and almost unlimited funding to design and build the world's first atomic bomb. To reduce the risk of failure, the project simultaneously developed two types of bombs based on the radioactive isotopes of either uranium 235 or plutonium 239. Both proved to be successful.

Also in 1942, Enrico Fermi and other scientists at the University of Chicago gave the project its first success by initiating a chain reaction in a nuclear reactor, using naturally radioactive uranium to fission in a controlled way. A nuclear reactor is a vessel that in its core contains fuel elements to provide fissionable material, control rods to absorb neutrons and slow the fission, and a moderator to reduce the energy of the neutrons, making them easier to capture in the fission process. Outside the core, reactors also need a way to extract the heat produced, normally using water, and shields to protect people and the environment from the radiation.

After the Chicago success, the project grew rapidly, locating bomb development and technical leadership in Los Alamos, New Mexico; uranium 235 development in Oak Ridge, Tennessee, and Paducah, Kentucky; and plutonium 239 development in Hanford, Washington. In just three years, progress had been so rapid that scientists exploded their first atomic bomb in July 1945 near Alamogordo, New Mexico, based on uranium 235.

In August 1945, two atomic bombs were dropped on Japan, one on the city of Hiroshima and the other on Nagasaki, causing horrible destruction in the two towns but compelling Japan to unconditionally surrender and bringing World War II to an end. Those two attacks remain the only two nuclear bombs actually used in a war, although many bombs were detonated between 1945 and the 1960s for testing purposes.

Post-World War II Development

During the 1950s, nuclear bomb development changed to fusion bombs, called thermonuclear or hydrogen bombs, rather than fission bombs because fusion created far more explosive energy. The fusion process uses extreme temperatures (greater then 10 million degrees) to force hydrogen isotopes like deuterium to fuse, forming helium and releasing even greater energy than from the fission process. Although the radioactive fallout from hydrogen bombs is somewhat less than from atomic bombs, damage from the blast is much worse and covers a much larger area. Many hydrogen bombs were successfully tested during the 1950s.

Not all nuclear weapons are designed for mass destruction. Some weapons, called tactical or theater nuclear weapons, are designed to be fired from cannons against relatively small military targets. Weapons of this type are capable of being distributed to armies in the field but are normally held in safe locations until their use has been approved by high-ranking military officials. The major concern with these weapons is that they can be stolen and sold to terrorist organizations that could then use them against the United States and other countries.

Nuclear technology also spread into other areas of military defense in the second half of the 20th century. Nuclear bombs are useless if they cannot be delivered to the intended targets, spawning much development for delivery vehicles, including long-range nuclear airplanes, submarines, and ships, using a nuclear reactor as the engine for these vehicles. Before large and accurate rockets became operational, a nuclear powered airplane was well into development, but the rockets offered a better solution.

Nuclear-powered submarines were mostly intended to be launching platforms for nuclear-tipped missiles, and many are currently operational. The U.S. Navy also developed nuclear-powered ships, most notably aircraft carriers and missile cruisers, to deliver both nuclear and conventional tactical weapons. Nuclear submarines were powered by specialized military reactors, but nuclear-powered ships were powered by nuclear reactors that were similar to those used to generate electricity in today's power stations.

Effects of Nuclear Bombs

Environmental damage from extensive use of nuclear bombs can be catastrophic for all living things. The first result from a nuclear explosion is to pump huge volumes of dust and vaporized matter high into the atmosphere to condense in a mushroom-shaped cloud. If enough bombs are exploded in a short time, a "nuclear winter" could occur that would block out the sun for weeks or months, most likely causing widespread crop failures.

In addition, much of the material pumped into the atmosphere is radioactive because normal matter that was picked up in the blast was converted to unstable isotopes, some of which could remain radioactive for many years. As the fallout from radioactive matter drifting back to earth settles on forests and agricultural areas, plants and animals can ingest the material, poisoning the world's food supplies. A widespread nuclear war could truly be called "a war to end all wars" because no one may be left to fight. Fortunately, public outrage and such arms reduction treaties as SALT I and SALT II are lessening the possibility of a nuclear war.

As a wholly new technology for the 20th century, nuclear energy rapidly established itself in applications relating to warfare but has been relatively slow to establish applications for peaceful uses, despite the contributions it has made to medicine. Large amounts of money have been spent to create valid peaceful uses, but problems of exceptionally high cost, significant environmental concerns, and other acceptable nonnuclear solutions have all limited its success. Also, the early use of nuclear bombs and the devastation they wrought resulted in emotional antagonism whenever a solution labeled "nuclear" was proposed. In time, the supply and environmental issues will become more balanced, and nuclear energy will possibly realize its full potential in contributing to American society.

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Further Reading

Bernards, Neal. Nuclear Power: Examining Cause and Effect Relationships. San Diego: Greenhaven Press, 1990; Dawson, Frank G. Nuclear Power: Development and Management of a Technology. Seattle: University of Washington Press, 1976; Joeck, Neil. Maintaining Nuclear Stability in South Asia. New York: Oxford University Press, 1997; Murray, Raymond LeRoy. Nuclear Energy: An Introduction to the Concepts, Systems, and Applications of Nuclear Processes. 6th ed. Burlington, VT: Butterworth-Heinemann/Elsevier, 2008; Pikayev, Alexander A., et. al. Russia, the U.S. and the Missile Technology Control Regime. New York: Oxford University Press, 1998; Tertrais, Bruno. Nuclear Policies in Europe. New York: Oxford University Press, 1999; Wolfson, Richard. Nuclear Choices: A Citizen's Guide to Nuclear Technology. Rev. ed. Cambridge, MA: MIT Press, 1993; Yost, David S. The U.S. and Nuclear Deterrence in Europe. New York: Oxford University Press, 1999.

MLA Citation

Marshall, Jim. "Nuclear Weapons." World History: The Modern Era, ABC-CLIO, 2019, worldhistory.abc-clio.com/Search/Display/309388. Accessed 15 Sept. 2019.

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Entry ID: 2174297

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