Tag Archives: atomic bomb

Bombing of Hiroshima

A short account of the bombing of Hiroshima

On the 6th August 1945, the USA dropped an atomic bomb nicknamed “Little Boy” on the Japanese city of Hiroshima from the B-29 aircraft Enola Gay.

70,000 people were killed instantly, of whom 20,000 were military personnel. Approximately another 70,000 died over the following months due to radiation sickness, burns, and other injuries directly related to the explosion.

The Potsdam Declaration issued on the 28th July by the Allies called for the unconditional surrender of Japan. If the government did not surrender they threated “the complete destruction of the Japanese armed forces and…utter devastation of the Japanese homeland”. Having completed the successful Trinity atomic test on the 16th July, the USA felt that the atomic bomb could quickly end the war in the Pacific.

Hiroshima was chosen as a target due to its industrial and military significance since it was the command centre for the defence of southern Japan and contained approximately 40,000 military personnel. The Enola Gay and six accompanying aircraft had a 6-hour flight from the air base at North Field, Tinian before reaching the city where they released the bomb at 8.15am. It exploded 600m above the city as planned, with the equivalent to 16 kilotons of TNT. Virtually all buildings within a mile of the blast were flattened.

Following the bombing, President Truman warned that if Japan did not surrender, “they may expect a rain of ruin from the air, the like of which has never been seen on this earth.” Japan did not surrender. A second bomb was dropped on Nagasaki three days later.

USSR nuclear test

The USSR’s first atomic test

On the 29th August 1949, the Soviet Union successfully detonated its first nuclear weapon codenamed RDS-1 and nicknamed First Lightning. The explosion had the power of 22 kilotons of TNT, and was 50% more destructive than its designers had expected.

The USSR started its nuclear program in 1943 after discovering the USA, Britain and Canada had begun bomb development. Assisted by intelligence from sources inside the USA’s Manhattan Project, the Soviet Union’s program developed quickly as the Soviets were able to replicate American successes while avoiding some of their costlier mistakes. Consequently, although the majority of Cold War academics accept that the USSR’s success had a lot to do with domestic expertise they recognise that intelligence helped to reduce the time it took for them to develop the bomb.

Work was accelerated after the bombings of Hiroshima and Nagasaki in secret, purpose-built cities dedicated to the nuclear program known as Atomgrads. By 1949 the Soviets had developed two types of bomb, but opted to detonate the simpler of the two designs first since it was similar in design to the successful Fat Man bomb that was dropped on Nagasaki.

The RDS-1 test was conducted in secret in an attempt to avoid the USA increasing its own nuclear program, but the US Air Force began to detect radioactive fallout from the explosion a few days later and tracked the trail. Soviet success had occurred up to 4 years ahead of Western estimates, and the knowledge that the USSR now had ‘the bomb’ dramatically increased tensions in the early years of the Cold War.

Rosenbergs

Why were the Rosenbergs sentenced to death? Overview podcast

Julius and Ethel Rosenberg met when they were members of the Young Communist League in New York. It was only after his previous membership of the organisation was discovered that Julius was dismissed from his position at the Army Signal Corps Engineering Laboratories at Fort Monmouth, New Jersey. He had worked as an engineer-inspector for nearly 5 years during the Second World War, and it was during this time that he was recruited to spy for Russia.

Rosenberg went on to recruit a number of other people who were able to supply secret information, including Ethel’s brother David Greenglass who worked on the Manhattan Project at the Los Alamos National Laboratory. He was arrested following a tip-off in May 1950, and named Julius Rosenberg as his contact.

During both a secret grand jury testimony and their subsequent trial the Rosenbergs refused to divulge information about their connections to the Communist Party. Despite this, they were found guilty of espionage and sentenced to death for their role in passing information about the US nuclear programme to the Soviet Union.

Although there have been subsequent attempts to clear their names, the publication of decrypted messages from the United States’ VERONA project in 1995 clearly showed that Julius Rosenberg was guilty of espionage and that Ethel was fully aware of her husband’s activities and actively assisted him. The general consensus among historians, therefore, is that the couple were guilty of the charge. However, debate still rages over whether or not their crime justified their executions.

US break relations with Cuba

Causes of the Cuban Missile Crisis

A chronological overview of the events leading to the Cuban Missile Crisis.