The Atomic Age: Historical Overview
Laying the scientific foundations, 1895 to 1932
Beginning in 1895 with Rontgen’s discovery of X-rays, scientists unraveled the
structure of the atom, revealing the electron and proton. During this
period they also discovered radioactivity and three of its components, alpha
and beta particles, and gamma radiation. The ability of X-rays to form
images of hidden objects such as the bones in a human hand fascinated the
public. Medical applications for radioactivity soon appeared.
The discovery of the neutron and fission, 1932 to 1939
In 1932 the final major component of the atom, the neutron, was discovered, and
in 1938 fission of uranium atoms by neutrons was carried out in
Germany. The energy associated with fission opened the possibility for
powerful weapons and also the production of energy for civilian use. The
world drifted toward another massive world war.
Alerting governments to the possibility of nuclear weapons, 1940 to 1943
Scientists in the United States, Great Britain, the Soviet Union, and Germany
recognized the potential for nuclear weapons offered by fission and took steps
to alert their governments. Each government responded differently due to
its economic, political, and military situation. The United States, assisted by
Great Britain, was in the best position to lay the scientific and technical
foundations for producing an atomic bomb.
The Manhattan Project, the atomic bomb, and the end of World War II, 1943 to
1945
Led by a group of eminent scientists, engineers, and army officers, the United
States produced fissionable materials and assembled them into the three atomic
bombs that were detonated in the summer of 1945. The decision to drop the bomb
was influenced by military and political events occurring throughout the war,
particularly in the final year of the struggle.
Domestic and international control of military and civilian use of nuclear
energy, 1945 to 1947
Domestic and international control of nuclear energy became a critical postwar
issue. The Atomic Energy Commission was formed and took over control of
all aspects of nuclear energy in the United States in 1947. The United Nations
attempted to develop a policy for control of nuclear weapons, but the United
States and the Soviet Union could not agree. This was but one component of the
emerging Cold War between the two nations. Citizens of all nations saw the
power of nuclear fission as massive threat as well as a source of useful energy
for mankind.
The initial years of the arms race and the hydrogen bomb, 1947 to 1952
In 1949, the Soviet Union exploded an atomic bomb and joined the race for
nuclear weapons. Britain followed in 1952. In the same year, the United
States detonated a thermonuclear device. The peaceful use of atomic energy for
electric power generation and medical applications was envisioned by the United
States and other nations.
The acceleration of the arms race to the Cuban Missile Crisis, 1953 to 1962
The arms race accelerated with the explosion of a thermonuclear device by the
Soviet Union in 1953. France became a nuclear power in 1960. Numerous nuclear
tests were performed by all the nuclear nations, and the total number of
weapons grew rapidly. The testing generated a fear of radioactive fallout in
the public and contributed to the debate on nuclear arms. The Cuban Missile
Crisis (1962) brought the world to the brink of nuclear war. Paradoxically this
confrontation caused the Soviet Union to build more missiles, while at the same
time it created pressure in both the United States and the Soviet Union for
control of nuclear weapons. During this period the United States proposed a
program to harness nuclear energy for peaceful purposes, and construction of
nuclear power plants began worldwide.
Nuclear treaties, mutually assured destruction, Three Mile Island and
Chernobyl, 1963 to 1986
In 1963 the Limited Nuclear Test Ban Treaty became the first agreement to
control nuclear weapons. China joined the nuclear powers in 1964.
The Non-Proliferation of Nuclear Weapons treaty was signed in 1968 by the
five nuclear nations and 180 non-nuclear nations. Next came the Strategic
Arms Limitation Talks (SALT I) signed by the United States and the Soviet Union
in 1972. SALT II followed it in 1979. The United States accelerated the
arms race with the Strategic Defense Initiative in 1983 and initiated Strategic
Arms Reduction Talks (START) with the Soviet Union during the mid 1980s to
limit nuclear warheads. The accidents at Three Mile Island in the United
States (1979) and Chernobyl, in the Ukraine (1986) had adverse effects on the
use of nuclear reactors for producing power
The end of the Cold War, disarmament, proliferation, and terrorism, 1986 to
2003
The fall of the Berlin Wall in 1989 symbolized the end of the Cold War, but
nuclear issues continued to be important. While the United States and Russia
continued to reduce their nuclear stockpiles, both retained massive
capabilities for nuclear destruction. In 1996 the United States signed the
Comprehensive Test Ban Treaty, but as yet Congress has not ratified it. The
management and disposal of radioactive waste from military and civilian
reactors became a major issue in the United States and Russia. Development of
nuclear weapons by India, Pakistan, Israel, and North Korea further alarmed the
world. By 2001, the acquisition of fissionable and radioactive materials by
terrorist groups also became a major threat to world order. The public
perception of nuclear threats, as reflected in political discourse, literature,
and film, had changed radically since 1945.
Timelines on the web
Three comprehensive timelines for the nuclear age are located at the following
web addresses: