The Cold War

(1945 - 1991)

Nuclear Age

Figure 1 Atomic bomb at Hiroshima Japan. Image. Britannica LaunchPacks, Encyclopedia Britannica, 8 Feb. 2020.

On August 9, 1945, three days after detonating a uranium-fueled atomic bomb over Hiroshima, Japan,

the United States dropped a plutonium-fueled atomic bomb over the Japanese port of Nagasaki.

Content Statement #22

The use of atomic weapons changed the nature of war, altered the balance of power, and began the nuclear age.

Content Elaborations

1. The dropping of the atomic bombs on Japan hastened the end of World War II and is considered the beginning of the nuclear age. Atomic bombs introduced a new type of weapon capable of mass destruction. Possession of the nuclear bomb contributed to the status of the United States as a superpower.

2. Successful Soviet development of the atomic bomb in 1949 escalated an arms race that continued throughout the Cold War and led to heightened fears of nuclear war and the establishment of the Soviet Union as a second superpower.

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Section A: United States as a Superpower

During World War II, the U.S. began a secret program known as the Manhattan Project to develop atomic weapons. The first atomic bomb was dropped on Hiroshima, Japan on August 6, 1945. This was followed by the dropping of the second atomic bomb on Nagasaki on August 9. The dropping of atomic bombs on Japan led to the rapid end of World War II in the Pacific. 

The use of atomic weapons changed the nature of war, altered the balance of power, and began the nuclear age. The dropping of the atomic bombs in Japan is considered the beginning of the nuclear period. The use of these bombs introduced a new type of weapon capable of mass destruction.

In the four years following World War II, the United States was the only country in possession of atomic bombs, and this contributed to its status as a superpower.

Nuclear Arms Race – American Timeline
1939	Albert Einstein and other scientists write a letter to President Roosevelt urging him to take steps to be at the forefront of nuclear weapons research so that other nations, such as Nazi Germany, don’t get there first.
1941	President Roosevelt authorizes funding in secret for the Manhattan Project; research begins at Columbia University and the University of California at Berkeley.
1942	The Manhattan Project relocates to Los Alamos, New Mexico.
1945	July: The Manhattan Project successfully tests the first Atomic Bomb.  President Truman informs Stalin that the US has successfully built an atomic bomb at the Potsdam conference thinking it would be a shock; Stalin already knew thanks to Soviet spies in the United States.
1945	August: The first two atomic bombs are dropped at Hiroshima and Nagasaki by the United States to end the war with Japan, the bombs kill approximately 200,000 people quickly.
1948	Cold War has begun between the US and the Soviet Union. One of the reasons attributed to the start of the Cold War was the fact that the US didn’t share atomic bomb-making technology with the Soviet Union, an ally at the end of WWII, but did share it with other allies, including Great Britain.
1949	NATO formed – a peacetime military alliance between the United States, Canada, and Western European countries for collective security
The late 1950s	Both the US and the Soviet Union have acquired enough nuclear power to obliterate the other side.

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Section B: Soviet Union as a Superpower

For four years following World War II, the United States was the only country in possession of atomic bombs. This contributed to its status as a global superpower. The threat of using this weapon was seen as a deterrent against the ambitions of the Soviet Union.

The testing and explosion of the atomic bomb by the Soviets in 1949 established the Soviet Union as a second global superpower. In 1952, the U.S. tested its first hydrogen bomb. Three months later, the Soviet Union tested its first thermonuclear bomb, and by using lithium, they made a bigger bomb small enough to fit into a plane. This nuclear arms race continued for decades and threatened world peace.

Nuclear Arms Race – Soviets Timeline
1948	Cold War has begun between the US and the Soviet Union. One of the reasons attributed to the start of the Cold War was the fact that the US didn’t share atomic bomb-making technology with the Soviet Union, an ally at the end of WWII, but did share it with other allies, including Great Britain.
1949	The Soviet Union tests its first atomic bomb.
1955	Warsaw Pact – Soviet bloc of collective security, a military alliance in response to NATO formed.
The late 1950s	Both the US and the Soviet Union have acquired enough nuclear power to obliterate the other side.

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Section C: Cold War Ideologies

Following World War II, the United States and the Union of Soviet Socialist Republics (Soviet Union) emerged as the two most influential powers in world affairs. The U.S. and Soviet Union had opposing political and economic ideologies. The U.S. was democratic and capitalist. The Soviet Union was communist. From 1945-1991, the two nations challenged one another in a series of confrontations known as the Cold War.

Not only did the US and USSR compete with one another in proxy wars, but they also engaged in a competition known as the Arms Race. Both countries looked to increase their nuclear stockpile with newer and more powerful weapons. However, neither side wanted to engage in a nuclear war that could destroy much of the world.

Cold War Ideologies
Key Areas	United States	Soviet Union
Economy	Capitalism · Private ownership of industry · Freedom of competition	Communism · Government ownership of industry · The goal is to bring economic equality to people
Politics	Democratic · Government by the people · Freedom of speech and press	Totalitarian · Government by one or a few · No freedom of speech or press
Key Values	Freedom · Based on individual rights	Equality · Everyone is equal
Society	Individual · Competition is the best way to get to the top · Stresses the need for people to do things on their own for themselves	Collective · “all for one, and one for all.” · Emphasizes the need for people to do things together to benefit the whole

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