On August 6 and 9, 1945, the US dropped two nuclear bombs on the Japanese cities of Hiroshima and Nagasaki , the only attacks of this nature ever carried out against human targets to date.
The approximate number of deaths accounted for by the bombings is 140,000 in Hiroshima and 74,000 in Nagasaki.
The Little Boy bombs , launched in Hiroshima, and the Fat Man , in Nagasaki, led the Japanese to declare their surrender on August 14, 1945, with the officialization on September 2 of the same year.
The attacks destroyed both cities, as well as sealing the end of World War II (1939-1945). With the bombings, the US sent a message to the world about the power of its war technology.
Other countries started nuclear projects in the following years, which led the world to experience the terror of a new and more powerful nuclear attack during the Cold War.
What led the United States to attack Japan?
The United States entered World War II only in 1941, after the Japanese attack on the American naval base at Pearl Harbor , which took place on December 7 of the same year.
Until then neutral, the North Americans maintained trade with the Allied countries (mainly France and England). This was one of the factors that led them to compose this group in the war.
Japan and the USA had diplomatic conflicts since the 1920s. During World War II, the Japanese invaded China and French Indochina, in 1941, in addition to the Philippine region, a territory under US control.
The US competed with the Japanese for hegemony on the Asian continent. Therefore, as a response during the war, the Americans imposed a trade embargo on the Japanese, vetoing the sale of essential items with them.
Japanese retaliation took place on December 7, 1941, when the Japanese attacked the US naval base at Pearl Harbor, without a declaration of war between the nations . This factor was decisive for the Americans to enter the war.
From then on, armed conflicts between the countries began. After a victorious Japanese start, the Asians were weakening economically and militarily, with defeat being an almost certain end.
Nuclear bombs
Manhattan Project
The Hiroshima and Nagasaki nuclear bombs were a result of the Manhattan Project. This top-secret American project brought together big names in science with the objective of developing nuclear weapons.
The US was afraid that Nazi Germany would produce this ordnance before the Allies. That's what Einstein and Szilard wrote in the letter sent to US President Franklin Delano Roosevelt, claiming that German scientists were already developing studies on nuclear fission.
The Manhattan Project developed during Roosevelt's administration, but he died on April 12, 1945, being his deputy, Harry Truman, the American president who authorized the dropping of the bombs.
The first nuclear bomb developed from the Manhattan Project was the Trinity , also the first to be detonated in the world. It was tested on July 16, 1945, a few months before the attacks on Japanese cities.
On July 26, 1945, Truman, in a speech, demanded the surrender of the Japanese, who had been weakened by the war. In an ultimatum, he stated that if the Asians did not surrender, they would face "rapid and absolute" destruction. .
Weeks later, the meaning of this phrase would become clear to the world. Seeing that the Japanese did not comply with the ultimatum, the Americans decided to attack.
Characteristics of dropped bombs and bombing chronology
The Little Boy , bomb used in Hiroshima , was three meters long by 70 centimeters in diameter and weighed four tons, with an explosive capacity of 15 tons of TNT.
The Fat Man , from Nagasaki , was 3.5 meters long and 1.5 meters at its maximum diameter, weighing 4.5 tons, composed of plutonium, with an explosive capacity of 20 tons of TNT.
The first city attacked was Hiroshima, on August 6, 1945. The B-29 bomber, named Enola Gay , piloted by Paul Tibbets, at 8:15 am, carried out the attack, launching the Little Boy , 253 uranium bomb. A strong flash formed with the explosion, creating a “little sun on Earth”.
The heat wave created by the bomb reached 4000 °C, reaching a radius of destruction of approximately 4.5 km. The force of the explosion could be felt from 60 km away.
For 3 days there were fires in the city caused by the heat. Approximately 60% of the city was destroyed and 140,000 people died in that first attack.
Despite the material, human and psychological impacts caused by an attack that shocked the world, Japan decided not to surrender. However, three days after the first attack, on October 9, the US dropped a second bomb.
The initial target was the city of Kokura, with a flat terrain, but the fog made it impossible for Charles Sweeney, pilot of the B-29 bomber (the same model used in Hiroshima), to drop the bomb.
So, he made his way to Nagasaki City loading the Fat Man , bomb with an even greater destructive power than the previous one, made of plutonium 239. The bomb exploded 500 meters from the ground.
The force of the Fat Man explosion was larger, but the geographic features of Nagasaki reduced the area of destruction, as there are two valleys between the city. Still, 40% of the city was destroyed.
Five days after the second attack, the Japanese declared their surrender on August 14, 1945. The agreement was signed on September 2, on the American ship USS Missouri, in Tokyo Bay.
The hibakushas , survivors of nuclear attacks and the nuclear fallout
Survivors of nuclear attacks are called hibakushas , Japanese word meaning "exposed to the bomb" or "sons of the bomb".
These individuals suffered from various health problems after the attack, with illnesses that manifested only years later due to radiation. In addition, cases of discrimination were commonplace.
Reports of hibakushas were common. struggling to find a job, get married or even marry their own children, due to people's fear of how the radiation would manifest itself in their bodies or genes in the future.
In addition to the deaths and destruction, the survivors were left with consequences such as first to third degree burns, retinal burns, cancerous tumors, genetic alterations, among other issues. In the long term, emotional problems, epidemic outbreaks of diseases such as tuberculosis, dysentery, hepatitis or other psychic and psychosomatic diseases.
In the environment, it was possible to notice climate changes, a growing and lasting increase in the flux of solar ultraviolet radiation and changes in temperature in different regions of the planet.
Interpretations on the American attack and the end of the Second World War.
The attacks on Hiroshima and Nagasaki are a point of discussion among historians. The Americans argue that the bombings ended a conflict that would last longer and cost more lives later.
However, researchers say that there was another objective: the US interest in demonstrating its technological power to the rest of the world, especially the USSR. This was evident with the Cold War Space Race.
About World War II
The Second World War was an armed conflict involving several countries that began in 1939 and ended in 1945. Two groups were formed:the Axis countries (Germany, Italy and Japan) and the Allies (England, France, USA and USSR) . Brazil was part of the second group.
At the end of the conflict, the Allied countries emerged victorious, leaving the Axis forces to lose territories and pay compensation.
Bibliographic References
RIBEIRO, Jayme. The "Sons of the Bomb":memory and history between the accounts of survivors of Hiroshima and Nagasaki and the "Campaign for the Prohibition of Atomic Bombs" in Brazil (1950). Other Times , Maranhão, Volume 6, number 7, July 2009 - History and Memory Dossier. Available at:https://www.outrostempos.uema.br/index.php/outros_tempos_uema/article/download/192/132/615. Accessed on September 5, 2022.