The atomic bombings of Hiroshima and Nagasaki were nuclear bomb attacks carried out by the United States on these Japanese cities, towards the end of World War II .

The attacks, ordered by US President Harry S. Truman , were carried out on August 6, 1945 on Hiroshima and on August 9 on Nagasaki . Together with the start of the Soviet-Japanese War, they were decisive in forcing the surrender of the Empire of Japan and the end of World War II.

The bombings of Hiroshima and Nagasaki were possible due to the success of the investigations of a team of scientists led by the American physicist Robert Oppenheimer, who secretly manufactured the first atomic bombs in history.

The attacks caused about 120,000 deaths at the time of the detonations, to which must be added the thousands of people who died later.

Today, the tributes that are made year after year to the victims of Hiroshima and Nagasaki revolve around the urgent need to abolish forever the use of all kinds of weapons of mass destruction.

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Historic context

Japan and the United States had been at war since late 1941, when the Japanese launched the surprise attack on Pearl Harbor , the American military base in the Hawaiian Islands. After this aggression, the United States entered World War II on the side of the Allies .

The Japanese continued the expansion process they had begun in 1937 and by early 1942 they dominated Korea, Manchuria, eastern China, the Philippine Islands, French Indochina, British Malaysia, Singapore, the Dutch East Indies, New Guinea, and various archipelagos of the Pacific.

In June 1942 the Americans defeated the Japanese in the decisive Battle of Midway , in which they managed to sink 4 enemy aircraft carriers. Midway put a brake on Japanese expansion. From then on, the United States, backed by its immense natural resources and its impressive productive capacity, was achieving victories and dislodging the Japanese from the archipelagos of Oceania.

In early 1945, the American fleet dominated the waters of the North Pacific. 40% of urban areas in Japan had been destroyed by aerial bombardments and industrial factories had been paralyzed by destruction and absenteeism from work.

At the end of June, the United States, after a bloody 80-day campaign, managed to take the island of Okinawa, located in southern Japan. A month later, on July 26, the allies issued the Potsdam Declaration , which urged Japan to surrender and claimed that failure to do so would result in “the inevitable and complete destruction of the Japanese armed forces and inevitably the devastation of the world. Japanese soil ‘.

As the Japanese government rejected the ultimatum, members of the US high command considered various alternatives to force the surrender of Japan, including a larger-scale landing than that of Normandy . But the one that finally prevailed was the option of an air attack with atomic bombs .

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Causes and consequences of Hiroshima and Nagasaki

Causes

Among the main causes of the atomic bombings of Hiroshima and Nagasaki are:

• The firm will of the Japanese government not to surrender , despite the capitulation of Germany in May 1945 and having no chance of winning the war.
• The calculations made by the US government about the costs of a possible invasion of Japan, which ranged from 250,000 to 500,000 casualties.
• The fear of suicide attacks by the Japanese, the so-called kamikazes. It was believed that if these attacks had been devastating in Pacific waters, they would be even worse in Japanese territory.
• The Soviet invasion of Manchuria , a region in which the Japanese had created the puppet state of Manchukuo. It began at midnight on August 9, hours before the attack on Nagasaki. Although this intervention had been agreed at the Yalta Conference , the Americans feared that Stalin would claim great territorial advantages if the Soviet presence became essential to force the surrender of Japan. Both the government and the US high command agreed that it was necessary to accelerate the end of the war to impose an armistice favorable to the interests of the United States.
• The desire of the contractors of the military industrial complex, of many members of the high command and of the American government, to experience in human beings the destructive power of the atomic bomb and to make a show of force before the Soviets, who were already shaping up to be the America’s main postwar rival.

Consequences

The main consequences of the atomic bombings of Hiroshima and Nagasaki were the following:

• The instantaneous death of some 120,000 people at the time of the detonations, to which must be added the thousands of people who died in the following weeks from injuries received and, later, due to diseases caused by exposure to radiation, among they leukemia, thyroid, breast and lung cancer. It is estimated that by the end of 1945 there had already been 246,000 deaths.
• The total destruction of the city centers of Hiroshima and Nagasaki , where almost no buildings were left standing. In Hiroshima 70% of the buildings were in ruins. In Nagasaki the damage was less, since the percentage of structures and buildings destroyed was 40%.
• The sufferings of the hibakushas (the survivors) for having witnessed the destruction of their homes, the loss of many loved ones and the fear of developing diseases due to radiation.
• The unconditional surrender of Japan announced on August 15, 1945, just 6 days after the detonation over Nagasaki. That surrender was formalized on September 2 with the signing of an act of capitulation. Thus ended the Second World War .
• The occupation of Japanese territory by allied forces consisting of troops from the United States, Great Britain, India, Australia, and New Zealand.
• Japan’s acceptance of the prohibition imposed by the United States on the manufacture or introduction of nuclear weapons in its territory.
• The beginning of a debate between defenders of the need for atomic bombings and their detractors. Those who defended the bombings on Hiroshima and Nagasaki pointed out that this accelerated the end of the war and saved the lives of hundreds of thousands of American soldiers. Among the critics, intellectuals like Albert Camus or scientists like Albert Einstein denounced the attack as an immoral act and accused those who authorized it of committing a crime against humanity. Other critics maintained that the atomic bombing was not necessary since Japan would have surrendered anyway in a short time.