Nuclear fall-out: how the USA & USSR became bitter enemies

In reality, though, the wartime alliance had been a marriage of convenience. The “main bond of the victors”, admitted Winston Churchill, had been “their common hate” towards Hitler’s Reich, but this no longer held them together after 1945. Three crunch issues lay at the heart of the ensuing Cold War: ideology, geopolitics and nuclear weapons.

Ideologically, America’s mantra was ‘liberty’ – ‘free enterprise’, limited government and democratic localism. Socialism and communism were minority movements in the USA, easily stigmatised as ‘un-American’.

In the USSR, Marxist-Leninist ideology predicted the imminent crisis of imperialist capitalism, leading to a dictatorship of the proletariat – of which the Soviet communist party constituted the vanguard. Although playing down the rhetoric of world revolution by the 1940s, Josef Stalin remained keen to accelerate the process of historical change. The chaos caused by the Second World War offered plenty of opportunities.

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In fact, the conflict transformed the geo­political position of both countries, sucking them into power vacuums created by the defeat of the Axis powers. These in turn became flashpoints of the new Cold War – above all, in Germany, China and Korea.

The USA and the USSR occupied Germany to defeat Adolf Hitler and then stayed to shape the peace. The Soviets had lost perhaps 27 million people from 1941–45, around one-seventh of their population, and were now determined to prevent the revival of German military power. But America and Britain were equally determined to get the country on its feet again and off their backs. In 1948, the US, Britain and France cut through the diplomatic deadlock and began to create a West German state out of their zones of occupation. They also introduced a new currency, the Deutschmark, which almost overnight got goods into the shops. Stalin hit back by blockading West Berlin, which the western allies could only reach through Soviet-occupied eastern Germany.

President Harry Truman had no doubt that remaining in Berlin had become “a symbol of the American intent” in Europe. And so, in tandem with the RAF, the US Air Force mounted a round-the-clock airlift of food and fuel into the beleaguered city in the winter of 1948–49. At its peak, Berlin was handling more air traffic than New York.

Berlin divided

The ‘air-bridge’ not only broke Stalin’s blockade, it also transformed West German attitudes to the Americans and British. Former enemies were now becoming allies, while the wartime allies were turning into adversaries. The blockade also widened the rift between the USSR and the other three victor powers. In April 1949, the US signed the North Atlantic Treaty with Canada and 10 European states, led by Britain and France. Stalin’s gamble in Berlin had boomeranged, drawing the west into an unprecedented transatlantic alliance.

Yet the global ‘correlation of forces’, as the Soviets called it, shifted again the following year. In October 1949, China’s three decades of civil war ended in total victory for Mao Zedong and the communists. The world’s most populous country had gone ‘red’ – arousing alarm and recrimination in America.

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An even greater shock followed in Korea. In 1945, Japanese forces had surrendered to the Soviets in the north and the US in the south. As in Germany, neither superpower was willing to withdraw. But their clients were determined to unify the country, and in June 1950 Stalin gave the green light to the North Korean leader Kim Il-sung to attack the south, thinking the west would not react. This was Stalin’s second gross miscalculation in two years: as with Berlin, Truman saw Korea as a vital symbol of US will and power. He judged that “communism was acting in Korea just as Hitler, Mussolini and the Japanese had acted 10, 15, 20 years earlier”. The lessons of appease­ment seemed clear: “If this was allowed to go unchallenged, it would mean a third world war.”

Truman committed US forces to Korea, enlisting the support of key allies, including Britain. The Korean War proved a yo-yo affair, with the North Koreans initially driving deep into the south before US counter-attacks pushed them back almost to the Chinese border. They in turn provoked China to enter the war. Fighting finally stabilised around the 38th parallel, which became the basis of an armistice in 1953. This agreement remains in force today in a country that remains divided. Korea was where the Cold War turned hot: the Americans lost 33,000; the Chinese perhaps half a million, including one of Mao’s sons; and the overall Korean death toll was maybe 2.5 million, a 10th of the population.

During the 1950s, other power vacuums opened up as decolonisation accelerated. Although the Japanese surrender in 1945 allowed the Europeans to recover most of their Asian domains, the days of empire were now numbered. The British conceded independence to India and Burma two years later, the Dutch gave up the East Indies (Indonesia) and France failed in its 1946–54 struggle to retain Indochina. Unwilling to see the whole region go communist, successive US presidents got sucked into a ‘quagmire’ war in Vietnam that eventually proved to be America’s greatest humiliation of the whole Cold War.

Hitherto the champion of liberty against the imperial powers, by the 1950s the US had to decide whether colonialism or communism was more distasteful and dangerous. Fearful of the growing reach of the left, Washington concluded that it was better to prop up colonial regimes and new post-colonial clients, resulting in US interventions in places like Iran in 1953 and Guatemala in 1954.

Atomic escalation

It was also during the 1950s that the nuclear arms race – the third hallmark of the early Cold War – became truly existential, with action and reaction its perpetual dynamic. In 1945, the explosion of two American atomic bombs on Japan had helped end the Asian war, but Stalin immediately made an A-bomb his top priority; in August 1949 the USSR successfully tested its first atomic device. Their atomic monopoly at an end, the Americans went all-out for a hydrogen bomb in 1952 – and the Soviets matched them in 1953.

The race then was to upgrade their ‘delivery systems’ from the era of air power into the missile age. This time the Soviets beat the Americans. Their launch of a man-made satellite, Sputnik, in November 1957 was both a technological humiliation for the USA and also a sign that the USSR had a sufficiently powerful rocket to launch a nuclear missile all the way to America. Eisenhower’s administration hastily accelerated its own missile programme and implemented a major scheme of civil defence.

Ideology, geopolitics and the bomb all fused together in the crisis over Cuba. Fidel Castro had seized power on the island in 1959, toppling a corrupt regime that was an American economic colony in all but name. Although Castro was not initially a Marxist, Washington’s reaction to his reforms drove him into the arms of Moscow. John F Kennedy inherited a half-baked CIA plan to topple Castro, using Cuban exiles in the US to avoid implicating the White House. But the ‘Bay of Pigs’ operation in April 1961 proved a fiasco – leaving the president’s macho brother Bobby fuming that JFK would now be “regarded as a paper tiger by the Russians”.

The competition deepened when Nikita Khrushchev, the feisty Soviet leader, got the better of Kennedy at a bruising summit in Vienna in June 1961. Pumped up by success, he introduced medium-range nuclear missiles into Cuba, just 90 miles off the coast of Florida.

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Unlike Stalin over Berlin in 1948, Kennedy was in a position to enforce a blockade of Cuba – controlling the surrounding air space and waters and, above all, enjoying huge superiority in nuclear arsenals if it came to all-out war. So Khrushchev decided to pull his missiles out of Cuba. But it had been a close-run thing. As secretary of state Dean Rusk put it, the two superpowers had been “eyeball to eyeball” and in the end it was the Soviets who “blinked”.

On 26 June 1963, Kennedy, now secure in his presidency, spoke in West Berlin. Two summers before, the Soviets and their East German allies had erected a wall to stop the flood of east Germans, mostly young, fit and educated, going west in search of freedom and prosperity. The wall ended the brain drain, but it proved a propaganda own-goal.

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Standing before a cheering crowd outside West Berlin’s city hall, Kennedy admitted that “freedom has many difficulties and democracy is not perfect”. But, he added, “we have never had to put a wall up to keep our people in”. To those who claimed not to understand what was at stake “between the free world and the communist world” the president issued this simple challenge: “Let them come to Berlin.”

As we now know, the Cold War still had a quarter-century to run, with many twists and turns. But that summer’s day in Berlin would define the rest of the struggle.

David Reynolds is professor of international history at Cambridge

This article was first published in the July 2016 issue of BBC History Magazine