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The Nuclear Age

West Berliner talks to the East, Berlin Wall, November 1962THE COLD WAR
Events > Postscript -- The Nuclear Age, 1945-Present

Joseph Stalin (with Vyacheslav Molotov), February 1945The postwar organization of atomic energy took place against the backdrop of growing tension with the Soviet Union.  Relations between the United States and the Soviet Union had been strained ever since the revolution of 1917 had first brought communists to power in Russia.  This mutual distrust further deepened following the Soviet "non-aggression" treaty with Nazi Germany in August 1939 and the Soviet Union's subsequent invasions of Poland, Finland, and the Baltic Republics.  Although Britain was allied with the Soviet Union following Germany's June 1941 invasion of Russia, as was the United States in the aftermath of Pearl Harbor, mutual suspicion lingered throughout the Second World War.  The failure of the United States and Britain to tell the Soviet Union about the atomic bomb in anything other than the most vague terms only heightened the extreme suspicions of the Soviet dictator, Joseph Stalin (right).  Not only did the atomic bombings of Hiroshima and Nagasaki help end the Second World War, but they also played a role in setting the stage for the half-century of conflict with the Soviet Union that followed it -- the Cold War.

In March 1946, the former British Prime Minister, Winston Churchill, warned that an "iron curtain" was descendingSecretary of State Dean Acheson signs the NATO Treaty while President Harry S. Truman looks on, April 4, 1949. across Eastern Europe as the Soviet Union imposed non-democratic communist governments on every nation under its military control.  A year later, President Harry S. Truman proclaimed the "Truman Doctrine," asking for funds for overseas military assistance to those governments that would oppose communism.  On the issue of international control of nuclear weapons, the United States, believing that the Soviet army posed a threat to Western Europe and recognizing that American non-nuclear forces had rapidly demobilized following the war, refused to surrender its monopoly on nuclear weapons without adequate controls.  In 1948 and 1949, the United States continued implementing its policy of "containment" of communism and the Soviet Union, most notably with the "Marshall Plan" to help rebuild the economies of Western Europe and with the North Atlantic Treaty Organization (NATO) designed to oppose any Soviet invasion of Europe.  In 1949, the Soviet Union tested its first atomic bomb (closely resembling the plutonium device tested at Alamogordo, thanks to espionage).  That same year, Chinese communists defeated their nationalist opponents in the Chinese Civil War.  By the time communist North Korea attacked American-backed South Korea in June 1950, many in the United States and around the world believed that a third world war was imminent or had already begun.  

B-29s on a bombing runIn this atmosphere of national emergency, government officials believed that continued American superiority in nuclear weaponry was vital to preventing a third world war.  If a global war should begin, American military planners hoped that continued nuclear superiority would allow the United States to strike the Soviet Union with such force that damage to the United States would be minimized and that Western Europe could eventually be reclaimed from an invading Soviet army.  The generation of United States Air Force generals who had overseen the aerial destruction of the cities of Germany and Japan was determined to prevent similar destruction of American cities.  In 1950, following the beginning of the Korean War and a secret governmental study called NSC 68, the United States nearly tripled its defense budget.  

Ivy Mike, the world's first thermonuclear (hydrogen bomb) test, November 1, 1952.The defense buildup of 1950-1951 included an expansion of the nuclear weapons complex and an increase of the stockpile of fission weapons.  Truman also approved the design and production of the next generation of nuclear weapons, thermonuclear weapons (the "hydrogen bomb").  When the United States tested the first of these on November 1, 1952 (right), the result was an explosion that was equivalent to one produced by more than ten million tons of TNT.  This was approximately 700 times the power of the uranium (fission) bomb dropped on Hiroshima.  In August 1953, the Soviet Union tested its first "boosted fission weapon," which used thermonuclear burning to enhance its yield, and in November 1955 the Soviet Union tested its first true thermonuclear weapon.  There was now almost no limit on the size of an explosion either superpower could create.  In August 1957, the Soviet Union tested the world's first intercontinental ballistic missile (ICBM), a feat dramatized two months later by the launch of the "Sputnik" satellite.  The following year, the United States first began limited operation of its own ICBM.  One of these nuclear-tipped missiles from either side could arrive at its target in less than an hour, and no defense was possible once the missile was launched.  The only thing thought now to be preserving the "delicate balance of terror" was the promise that if one nation attacked, the other would surely retaliate.  The era of "mutual assured destruction," or "MAD," had dawned.  

Soviet R-7 ICBM (the type that launched Sputnik)No global third world war ever took place.  Mindful that a full-scale nuclear exchange would be a disaster for both sides, the superpowers fought each other through a variety of proxy wars and "shadow struggles" in Korea, Vietnam, Afghanistan, and dozens of other places.  The strategy of the United States and its like-minded allies was to use the nuclear threat to avert a direct Soviet attack on Western Europe and allow time for the eventual internal reform or even collapse of the Soviet Union and its satellite states.  Events eventually confirmed this strategy, but the Soviet Union in the interim proved willing to use overt military force to prevent the collapse of communist governments, most notably with its invasions of Hungary in 1956 and Czechoslovakia in 1968.  At the same time, the Soviet Union supported the spread of communism through insurrections and the overthrow of pro-western regimes in the third world.  The United States, in turn, responded with economic and military aid and, where necessary, armed force to prop up friendly governments and used its own secret intelligence services in attempts to overthrow unfriendly governments.

United States Marine in Korea, December 1950After four decades of an enormously expensive arms race, the Soviet economy in the 1980s finally collapsed.  Once it became clear that the Soviet Union would no longer intervene militarily, the people of Eastern Europe overwhelmingly rejected communism in a wave of mostly peaceful revolts throughout 1989 and 1990.  When the Russian people were finally allowed to participate in a democratic election, they too rejected communism, weary as they were of more than seven decades of repressive and sometimes murderous governments.  The peoples of other nations that had been forced to join the Soviet Union -- from the Baltic Republics to Ukraine to the Caucasus Mountains to the steppes of Asia -- chose to leave the Soviet Union completely.  On Christmas Day, 1991, the Soviet flag was lowered for the last time over the Kremlin, and the Soviet Union officially ceased to exist.  

President Ronald Reagan talks to the East, Berlin Wall, June 12, 1987This "victory" did not come cheap.  Millions died in the wars fought in Korea, Vietnam, Afghanistan, and elsewhere.  Untold wealth, which could have been put toward any number of social or humanitarian needs, was expended on military manpower and sophisticated weaponry.  Nor was victory foreordained.  No one knew for certain whether communism would not prove to be the inevitable wave of the future or if the ideological struggle would not all end in a massive nuclear exchange spawned by accident or desperation.  

The nuclear weapons designed, built, and tested by the Manhattan Project and its lineal descendents were perhaps the single most defining element of the second half of the twentieth century.Ivy King nuclear test, November 15, 1952 At the same time that they visited on the world unprecedented fear and a daily awareness of the nearness of global holocaust, nuclear weapons also bought the necessary time to achieve a successful outcome to the Cold War on the basis of ideology, economics, social structure, and the limited application of military might.  In the over half-century since the Manhattan Project, the world has seen no wars that have even come close to matching the death and destruction associated with the two world wars of the early part of the century.  Perhaps Robert Oppenheimer's wish for a weapon that was so terrible that war itself would become obsolete was not entirely without hope.

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Sources and notes for this page.

Most of the text for this page is original to the Department of Energy's Office of History and Heritage Resources.  Parts were adapted from, and portions were taken directly from, the History Office publication: Terrence R. Fehner and F. G. Gosling, Origins of the Nevada Test Site (DOE/MA-0518; Washington: History Division, Department of Energy, December 2000), 86-87.  The phrase "the delicate balance of terror" is from Albert Wohlstetter's famous article of the same name, Foreign Affairs 37 (January 1959), 211-234.  The photographs of the Berlin Wall in 1962 and of Dean Acheson signing the NATO Treaty are courtesy the North Atlantic Treaty Organization (NATO).  The photograph of Joseph Stalin with Vyacheslav Molotov is courtesy Roosevelt Presidential Library (via the National Archives (NARA)).  The photograph of the B-29s over Korea is courtesy NARA.  The photograph of the Berlin Wall in 1987 is courtesy the White House Photographic Office (via NARA).  The photograph of the Marine in Korea is courtesy the Office of the Secretary of the Air Force (via NARA).  The photograph of the Soviet R-7 ICBM is courtesy the Federation of American Scientists.  The photograph of the Ivy Mike thermonuclear (hydrogen bomb) test and the Ivy King nuclear test are courtesy the Department of Energy's Nevada Site Office.

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