In pictures: The history of the Cold War

The decision by the United States to use the atomic bomb against Japan in August 1945 was credited with ending World War II. Hundreds of thousands in Hiroshima and Nagasaki were killed instantly or died from radiation in the aftermath of the bombings.

British Prime Minister Winston Churchill delivers a speech at Westminster College in Fulton, Missouri, on March 5, 1946. "From Stettin in the Baltic to Trieste in the Adriatic, an Iron Curtain has descended across the Continent," he declared.

On June 24, 1948, the Soviet Union made a bid for control of Berlin by blockading all land access to the city. Berlin was divided into four sectors under US, British, French and Soviet control, but the city itself lay entirely in Soviet-occupied eastern Germany. From June 1948 to May 1949, US and British planes airlifted 1.5 million tons of supplies to the residents of West Berlin. After 200,000 flights, the Soviet Union lifted the blockade. Here, a tattered group of Berliners stand amid the ruins of a building near Tempelhof Airfield as a C-47 cargo plane brings food to the city.

In August 1949, President Harry Truman signed the North Atlantic Treaty, which marked the beginning of NATO. Two years earlier, he requested $400 million in aid from Congress to combat communism in Greece and Turkey. The Truman Doctrine pledged to provide American economic and military assistance to any nation threatened by communism.

Joseph Stalin, left, meets with Mao Zedong in Moscow in December 1949. In June 1949, Chinese Communists declared victory over Chiang Kai-shek's Nationalist forces, who later fled to Taiwan. On October 1, Mao Zedong proclaimed the People's Republic of China. Two months later, Mao traveled to Moscow to meet with Stalin and negotiate the Sino-Soviet Treaty of Friendship, Alliance and Mutual Assistance.

On June 25, 1950, North Korean Communist forces invaded South Korea. Two days later, President Truman ordered US forces to assist the South Koreans. Here, US Marines land at Inchon as battle rages. Three years later, an armistice agreement was signed, with the border between North and South roughly the same as it had been in 1950. The willingness of China and North Korea to end the fighting was in part attributed to the death of Stalin in March.

School children learn to protect themselves in case of nuclear attack by practicing a duck-and-cover drill in their classroom in 1951.

Stalin's body is seen in his coffin after his death on March 5, 1953, after suffering a stroke. The Soviet Communist leader's embalmed body was on display until 1961.

On March 29, 1951, Julius and Ethel Rosenberg were convicted of selling US atomic secrets to the Soviet Union. The Rosenbergs were sent to the electric chair in 1953, despite outrage from liberals who portrayed them as victims of an anti-communist witch hunt.

The Rosenbergs' conviction helped fuel the rise of McCarthyism, the anti-communist campaign led by US Sen. Joseph McCarthy of Wisconsin in the 1950s. Nearly 400 Americans -- including the ordinary, the famous and some who wore the uniform of the US military -- were interrogated in secret hearings, facing accusations from McCarthy and his staff about their alleged involvement in communist activities. While McCarthy enjoyed public attention and initially advanced his career with the start of the hearings, the tide turned. His harsh treatment of Army officers in the secret hearings precipitated his downfall.

On October 4, 1957, the Soviet Union launched Sputnik, the first man-made satellite to orbit the Earth. In 1958, the United States created NASA, the National Aeronautics and Space Administration, and the space race was in full gear.

In 1959, leftist forces under Fidel Castro overthrew the government of Fulgencio Batista in Cuba. Castro soon nationalized the sugar industry and signed trade agreements with the Soviet Union. The next year, his government seized US assets on the island.

Soviet leader Nikita Khrushchev speaks at the 1960 Paris Summit, which was interrupted when an American high-altitude U-2 spy plane was shot down on a mission over the Soviet Union.

U-2 spy plane pilot Francis Gary Powers poses with his flight helmet among other evidence related to his Moscow trial in 1960. After the Soviets announced the capture of Powers, the United States recanted earlier assertions that the plane was on a weather research mission.

On April 12, 1961, Soviet cosmonaut Yuri Gagarin circled the Earth aboard a spacecraft called Vostok 1. After parachuting from the craft near the Russian village of Smelovka, Gagarin landed a hero — and a major embarrassment for the United States, already stung by the Soviet first-in-the-race launch of the Sputnik 1 satellite four years earlier.

A young woman, accompanied by her boyfriend, stands at the Berlin Wall to talk to her mother on the East Berlin side in 1962. The wall divided the eastern and western sectors of the city. The US had rejected proposals by Soviet leader Nikita Khrushchev to make Berlin a "free city" with access controlled by East Germany, and in August 1961 Communist authorities began construction on the wall to prevent East Germans from fleeing to West Berlin.

Reporters take pictures of US President John F. Kennedy behind his desk after he signed the arms embargo against Cuba in 1962. The embargo effectively quarantined Cuba. In 1961, a US-organized invasion of 1,400 Cuban exiles was defeated by Castro's forces at the Bay of Pigs. President Kennedy took full responsibility for the disaster. The next year, the Soviet Union installed nuclear missiles on Cuba capable of reaching most of the US. Kennedy ordered a naval blockade of Cuba until the Soviets removed the missiles. Six days later, the Soviets agree to remove the missiles, defusing one of the most dangerous confrontations of the Cold War.

The Soviet cargo ship Fizik Kurchatov leaves Cuba en route for Russia in 1962, during the Cuban missile crisis. On deck are six canvas-covered missile transporters with missiles.

US troops were sent to South Vietnam in 1965 after it was alleged that North Vietnamese patrol boats had fired on the USS Maddox in the Gulf of Tonkin. The Vietnam War lasted nearly a decade and left more than 58,000 Americans dead.

Missile launchers are on display during a military parade in Moscow's Red Square in 1967.

A young Czech woman shouts "Ivan go home!" to soldiers sitting on tanks in the streets of Prague in 1968. On January 5, 1968, reformer Alexander Dubcek became general secretary of the Communist Party in Czechoslovakia, pledging the "widest possible democratizations" as the Prague Spring movement swept across the country. Soviet and Warsaw Pact leaders sent an invasion force of 650,000 troops in August. Dubcek was arrested and hard-liners were restored to power.

Apollo 11 astronaut Edwin E. "Buzz" Aldrin Jr. walks on the lunar surface on July 20, 1969. He and mission commander Neil Armstrong became the first humans to walk on the moon. Their mission was considered an American victory in the Cold War and subsequent space race, meeting President Kennedy's goal, voiced in 1961, of "landing a man on the moon and returning him safely to the earth" before the end of the decade.

With Kremlin leaders and Presidential aides looking on, US President Richard Nixon shakes hands with Communist Party Chairman Leonid Brezhnev after signing one of several agreements made during their seven-day summit in 1974.

Afghan rebels are seen on top of a knocked out Russian armored vehicle in Afghanistan in February 1980. The Soviet Union invaded Afghanistan in 1979 as communist Babrak Karmal seized control of the government. US-backed Muslim guerrilla fighters waged a costly war against the Soviets for nearly a decade.

Balloons are released during the opening ceremony for the 1984 Summer Olympics in Los Angeles. After the US boycotted the Moscow Summer Games in 1980, Eastern Bloc countries — including the Soviet Union and East Germany — boycotted the 1984 Games.

US President Reagan, commemorating the 750th anniversary of Berlin, addresses the people of West Berlin at the base of the Brandenburg Gate, near the Berlin Wall on June 12, 1987. Due to the amplification system being used, the President's words could also be heard on the Eastern (communist-controlled) side of the wall. "Tear down this wall!" was the famous appeal by Reagan, directed at Gorbachev, to destroy the Berlin Wall. The address Reagan delivered that day is considered by many to have affirmed the beginning of the end of the Cold War and the fall of the Soviet bloc.

President Reagan and Soviet leader Mikhail Gorbachev sign the arms control agreement banning the use of intermediate-range nuclear missiles in December 1987.

A demonstrator pounds away at the Berlin Wall in November 1989. Gorbachev renounced the Brezhnev Doctrine, which pledged to use Soviet force to protect its interests in Eastern Europe. In September, Hungary opened its border with Austria, allowing East Germans to flee to the West. After massive public demonstrations in East Germany and Eastern Europe, the Berlin Wall fell on November 9.

Jubilant people step on the head of the statue of Felix Dzerzhinsky, the founder and chief of the Soviet secret police, later known as KGB, which was toppled in front of the KGB headquarters in Moscow on August 23, 1991. The KGB was responsible for mass arrests and executions.

Russian Federation President Boris Yeltsin, left, and Soviet President Gorbachev look over a document while attending the Congress of People's Deputies in Moscow in September 1991. While vacationing in the Crimean peninsula, Gorbachev was ousted in a coup by Communist hard-liners on August 19, 1991. The coup soon faltered as citizens took to the streets of Moscow and other cities in support of Yeltsin, who denounced the coup. Yeltsin was the first democratically elected president of Russia.

In this photo of a TV screen, Gorbachev announces his resignation on December 25, 1991, ending his nearly seven years of power and signaling the end of the Soviet Union.

The Russian flag flies over the Kremlin shortly after Gorbachev resigned. The red Communist flag bearing the gold hammer and sickle emblem that fluttered over the Kremlin came down in a final act that underscored the fall of the Soviet Union -- and the end of the Cold War.