The 16th July 1945 marked the start of the atomic age when the USA detonated the first nuclear bomb under the codename ‘Trinity’. Nicknamed ‘the gadget’ by the people working on it, the plutonium-based weapon was detonated at the Alamogordo Test Range in New Mexico. The explosion was equivalent to about 20 kilotons of TNT, and the blast-wave was felt by civilians up to 160 miles away. To maintain secrecy, a press release was issued shortly after the successful detonation that claimed a large ammunition storage magazine had exploded.

The development of nuclear weapons by the US Army in the Manhattan Project that began in 1942 at Los Alamos Laboratory in New Mexico started due to concerns that Nazi Germany would develop an atomic bomb. By 1944 scientists had designed an implosion-type device and proposed that a test take place. The location was chosen in September, and an on-site laboratory was set up.

President Truman was keen to test the bomb before the Potsdam Conference began on the 18th July, so the 16th was chosen to give time to try again in case it failed. However when the appointed hour came rain was falling, which would have increased radioactive fallout, and so the detonation time was pushed back from 4am to 5.30am. At 5:29am the “the gadget” was exploded on top of a 100-foot steel tower, known as Point Zero. J. Robert Oppenheimer, the director of the Los Alamos Laboratory, later said that after the explosion he recalled a verse from Hindu scripture: ‘Now I am become Death, the destroyer of worlds.’

Henry Kissinger, Richard Nixon’s National Security Advisor, made a secret trip to China to meet with Premier Zhou Enlai.

Even before Nixon became president in 1969 he had expressed a desire to improve American relations with China. The USA had been virtually isolated from China since the Communists came to power in 1949, and Nixon was keen to end these two decades of mutual hostility. While part of his motivation was to contain China’s potential nuclear threat, he also sought to use China to find a way to end the Vietnam War while exploiting the increasingly poor relationship between China and the USSR.

Kissinger was given the delicate task of making contact with the Chinese government and, following the Chinese invitation to the American ping pong team in April 1971, it was clear that China was also interested in improving the relationship. However, without any direct channels of communication between the two countries, Kissinger was forced to use Pakistan as a third party through which the diplomatic visit would be organised.

Kissinger set out on a publicly announced trip to Vietnam, Thailand, India, and Pakistan in early July 1971. At the conclusion of his meetings in Pakistan, it was then announced that Kissinger was ill and would recuperate in a hill station. In reality the motorcade was a decoy, since Kissinger and a small group of advisors had boarded a Pakistani plane to Beijing.

They landed at noon, and spent a total of 49 hours in China. During this time they held a series of talks with the Chinese government that set out the parameters for a visit by President Nixon himself. On 15 July Nixon appeared on television from the Oval Office to announce that he would visit China the following year.

On the 4th July 1950, Radio Free Europe – founded the previous year to transmit uncensored information to audiences behind the Iron Curtain – completed its first broadcast. Although the station was uncensored in the sense that it shared information that was suppressed within the Communist Bloc, it’s important to remember that it was still a propaganda tool founded and principally funded by the United States government.

The task facing the journalists who worked for RFE was daunting. Since they broadcast to states that suppressed a range of information and news, the gathering of intelligence to provide broadcast material was an enormous challenge. They often relied on risky contact with émigrés and people who had traveled behind the Iron Curtain for eye-witness accounts, and closely monitored print and electronic media from the communist governments. It’s even been suggested that the quality and quantity of information was so comprehensive that the communist governments themselves used Radio Free Europe to gain information about what was happening within their own countries.

However, RFE was still fundamentally a broadcaster that promoted anti-communist ideas and was therefore a significant threat in the countries it targeted. The USSR tasked the KGB with establishing expensive radio jamming facilities to try to block broadcasts, while in 1981 a terrorist group funded by the Romanian regime of Nicolae Ceaușescu detonated a bomb at RFE’s Munich headquarters.

Despite these challenges Radio Free Europe and its partner station Radio Liberty continued broadcasting, and even after the end of the Cold War has continued to broadcast to countries where a free press is not established.

US President Harry S. Truman ordered air and naval forces to assist South Korea against an invasion by North Korea.

Towards the end of the Second World War in 1945 the ‘big three’ powers of the USA, the USSR and Great Britain met at the Yalta Conference. As part of a wide-ranging series of agreements, Korea was divided along the 38th parallel with a Soviet occupied zone in the north and Americans in the south.

In May 1948 the north, led by Kim Il-sung, declared itself the communist Korean Democratic People’s Republic. The democratic Republic of Korea soon followed in the south, and within a year both the USSR and the USA had withdrawn the majority of their troops. Meanwhile, the two Korean nations claimed the right to rule the other.

In the early morning of 25 June, North Korean troops crossed the 38th parallel and invaded South Korea. The action was condemned later that afternoon by the United Nations Security Council, who issued UN Security Council Resolution 82 which called for the North to immediately draw back to the 38th parallel. Two days later, on 27 June, the Security Council approved Resolution 83 which recommended providing military assistance to South Korea. The USSR could have been expected to veto both of these resolutions, but at the time was boycotting the Security Council over its refusal to admit the newly-proclaimed People’s Republic of China.

Truman announced American intervention shortly after Resolution 83 to broad approval from both Congress and the public. Fighting continued until 27 July 1953 when an armistice was signed that established the Korean Demilitarized Zone along the 38th parallel. A peace treaty was never concluded.

On the 26th June 1963 American President John F. Kennedy declared US support for West Berlin with the phrase, “Ich bin ein Berliner” – I am a Berliner – 22 months after the Soviet-supported DDR, more commonly known as East Germany, built the Berlin Wall.

Berlin had been a focal point for Cold War tensions ever since the Yalta and Potsdam conferences in 1945 divided the city – and the rest of Germany – between the four victorious powers at the end of the Second World War. When the USSR imposed the Berlin Blockade from 1948-49, the Western allies made it clear that they were not willing to back down in their support for West Berlin by airlifting supplies into the city.

Although the airlift secured West Berlin’s survival, it further increased tensions between the USSR and its former allies as East Germans crossed the border in order to defect to the West. This placed an enormous economic strain on the East, which began suffering labour shortages. In response, the government of East Germany erected a barbed wire fence around West Berlin that eventually developed into the imposing Berlin Wall, although the government claimed that it was to keep out spies and agitators rather than stop people from leaving.

It was against this background of heightened tension that Kennedy delivered his rousing speech on the steps of the Rathaus Schöneberg, the seat of the state senate of West Berlin. While the speech effectively recognised East Berlin as part of the Soviet Bloc, it also reaffirmed America’s commitment  to defend West Berlin against Communist expansion.

On June 16th 1958, Hungarian Communist politician Imre Nagy was executed. Arrested after Soviet forces brought the Hungarian Revolution of 1956 to an end, Nagy was found guilty of treason in a secret trial and executed by hanging.

Nagy had been sacked from his position as Chairman of the Council of Ministers in April 1955 due to his independent attitude that favoured a “New Course” in Socialism. Although his moderate reforms were met with hostility from the USSR, they garnered significant support within Hungary where opposition to the hard-line government of Mátyás Rákosi had grown since the death of Stalin in 1953. Nagy’s popular support led to him being appointed Prime Minister on October 24th 1956, the day after the Revolution began.

After a week of violence, Nagy recognised the crowd’s desire for political change. Despite being an ardent Marxist he began moves towards introducing a multiparty political system and, on November 1st, announced Hungary’s withdrawal from the Warsaw Pact and its status as a neutral country. This proved too much for Khrushchev in the USSR, who moved his troops into Budapest and seized control of most of the city by the 8th November. Nagy took refuge in the Yugoslavian embassy, but was arrested when he was given false promises of safe passage to leave Hungary on the 22nd November.  He, and other leading members of the deposed government, were imprisoned in Romania until 1958 when they were returned to Hungary for trial.

News of Nagy’s trial and execution were only made public after the sentence had been carried out.

On the 8th June 1972 one of the most iconic photographs of the Vietnam War was taken of Phan Thị Kim Phúc, a nine-year-old girl from the South Vietnamese village of Trang Bang. In the photograph, she is shown running away from a napalm attack, having stripped off her clothes after being severely burned.

The photograph, which went on to win a Pulitzer Prize, was taken by Nick Ut, a Vietnamese photographer for the Associated Press. He was one of number of press photographers who were with the group of fleeing civilians after the village had been bombed South Vietnamese planes. He took Kim Phúc and other injured children to a hospital in Saigon before delivering the film to be developed, and maintained contact with her throughout her recovery despite being told that her burns were so severe she was unlikely to survive.

The photograph was initially rejected by Associated Press due to the full-frontal nudity. However, the image was deemed to capture such a powerful news story that these concerns were put aside. When the picture appeared on the front page of the New York Times four days later, it had such a dramatic impact that President Nixon discussed with his chief of staff whether the shot had been ‘fixed’.

Kim Phúc stayed in hospital for 14-months, and underwent 17 surgical procedures and skin transplants before she was able to return home. However she did survive and – having sought political asylum in Canada during an aircraft refuelling stop on her honeymoon – she now lives in Ontario.

On the 25th May 1961, American President John F. Kennedy made the announcement to a joint session of Congress that he had set his sights on a manned moon landing before the end of the decade.

To many people, including some personnel at NASA, Kennedy’s address seemed ridiculous. The USA had only sent its first man into space 20 days earlier and, although Alan Shepard’s spaceflight aboard Freedom 7 was a huge success, the USSR’s Yuri Gagarin had already become the first man in space three weeks before that. Taking on the USSR at a technological game that they were already leading appeared reckless.

An underlying issue was that, as part of his election campaign, Kennedy had promised to outperform the Soviet Union in the fields of space exploration and missile defence. In his famed television debate with Richard Nixon, Kennedy had mocked the fact that Nixon was proud of the USA being ahead of the USSR in terms of colour television while trailing in terms of rocket thrust. Gagarin’s flight had proved to the world that the USSR was currently ‘winning’ the Space Race, and so put pressure on Kennedy to increase spending on the Apollo space program.  Having received a memo from Vice-President Lyndon B. Johnson in which he reported that the USA was unlikely to ever outperform the USSR under the current spending arrangements, Kennedy launched the largest peacetime financial commitment ever made.

The $24 billion dollars did work, however, and Apollo 11 achieved Kennedy’s goal by landing on the moon on 20th July 1969.

The USSR and seven other European countries signed the Treaty of Friendship, Cooperation, and Mutual Assistance better known as the Warsaw Pact.

The Warsaw Pact was established shortly after West Germany was admitted to NATO. The USSR was concerned by the remilitarisation of West Germany, something it had tried to avoid when it proposed a new European Security Treaty that failed to gain support from the Western powers in November 1954.

Just five days after West Germany joined NATO representatives of the Soviet Union, Albania, Poland, Romania, Hungary, East Germany, Czechoslovakia, and Bulgaria met in Warsaw where they signed the treaty. While the agreement established a system of collective security between the member states it also set up a unified military command under the leadership of the Soviet Union.

The Pact permitted Soviet troops to be garrisoned on satellite territory, consequently strengthening Soviet control over the Eastern Bloc and acting as a military counterpart to Comecon, the socialist economic organisation that had been established in 1949.

The presence of Soviet troops was a contributing factor to the 1956 uprisings in both Hungary and Poland. Both these countries did, however, take part in the Warsaw Pact invasion of Czechoslovakia in 1968 that ended the Prague Spring. Only Romania and Albania refused to join the invasion, the latter subsequently withdrawing completely from the pact.

The Warsaw Pact was formally declared “nonexistent” on 1 July 1991, although in practice it had been in decline for two years as a result of the overthrow of communist governments in the member states that had begun in 1989.

On 29th April 1975, America began Operation Frequent Wind – the evacuation of over 1,000 American civilians and a further 6,000 “at-risk” Vietnamese from Saigon.  The largest ever helicopter evacuation lasted for 19 hours and involved 81 helicopters shuttling the evacuees to US Navy ships moored in the South China Sea.

With North Vietnamese troops closing in on the capital by March 1975, the US had already evacuated 45,000 people by April 29th.  However, with fixed-wing evacuations impossible due to the approaching army, US Ambassador Graham Martin ordered the commencement of Operation Frequent Wind.  American Forces Radio made their pre-arranged signal “The temperature in Saigon is 105 degrees and rising”, and followed it by playing Bing Crosby singing White Christmas.  The evacuation began at around 2pm.

The main muster point was the Defense Attaché Office, from where thousands of people were successfully airlifted in a relatively orderly manner.  However, at the US Embassy thousands more people had gathered – considerably more than it would be possible to evacuate even with helicopters landing every 10 minutes.

With hundreds of eligible Vietnamese civilians still at the Embassy, at 3.27pm President Ford ordered Ambassador Martin to stop evacuating anyone other than American personnel.  The Marines guarding the compound were ordered to move further inside, and shortly afterwards the crowds broke through the gates.  The last of the Marines were flown out at 7.53am, leaving approximately 400 evacuees still inside the Embassy when it fell to the Communists.