Why Did the US Drop Atomic Bombs on Hiroshima and Nagasaki? | History Hit

Why Did the US Drop Atomic Bombs on Hiroshima and Nagasaki?

Harry Atkins

20 Jun 2018
Atomic cloud over Hiroshima, 6 August 1945
Image Credit: National Archives

The question of whether or not the United States was right to drop atomic bombs on the Japanese cities of Hiroshima and Nagasaki in August 1945 is surely among the 20th century’s most enduring and divisive.

For many, the horrors inflicted by an atomic attack are so devastating and widespread that there will never be any justification. Others, however, will claim that war invariably demands unpalatable actions to bring about an end to conflict.

At 11.02 am on August 9 1945, America dropped the world's most powerful atomic bomb on Nagasaki. The Japanese port city was flattened to the ground 'as if it had been swept aside by a broom', with over 70,000 people killed. At that time, hundreds of Allied prisoners of war were working close to the bomb's detonation point, as forced labourers in the shipyards and foundries of Nagasaki. Having survived four years of malnutrition, disease, and brutality, they now faced the prospect of the US dropping its second atomic bomb on their prison home. In this episode James is joined by John Willis, whose new book Nagasaki: The Forgotten Prisoners paint a vivid picture of defeat, endurance, and survival against astonishing odds. Warning: The events recounted in this episode may be distressing to some listeners
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The main reasons given

To better understand whether atomic action was justified in 1945, we must first consider the likely motivations behind it. The main reason given for America’s decision to take atomic action is that it was a way to conclude the war without suffering further losses (on the American side at least).

There are also those who see the attacks as retribution for Pearl Harbour and the many American lives lost in bloody warfare with Japan.

We might also consider the geopolitical impact that the Hiroshima and Nagasaki attacks had at a time when tensions were rising between the US and the Soviet Union. As a signal of American military might, the atomic attacks on Japan were undoubtedly emphatic, especially at a time when the Soviet Union lagged behind the US in the race for nuclear armament.

The attack on Pearl Harbour

The case for the attacks ending the war

The most commonly expressed justification for the Hiroshima and Nagasaki bombings has been that they brought a halt to a war that would have otherwise claimed many more lives. It was believed that America’s only alternative to an atomic assault was an invasion of Japan, which would have almost certainly involved the loss of thousands more US soldiers.

The bombings, remember, followed a long period of conflict that had already seen 418,000 Americans killed.

Recent battles with Japan at Iwo Jima and Okinawa had proved extremely costly for the US in terms of casualties and, despite Japan’s weakened military position, there was a strong sense that the Japanese would not lay down without a bloody fight. The shock of Japanese kamikaze attacks had not helped this impression.

In such circumstances, the US decided that a significant Japanese death toll was a justified means to an end. Indeed, it would have been politically difficult for President Harry S. Truman to make any other decision.

Truman had assembled a committee, chaired by Secretary of War Henry Stimson, to consider the question of an atomic assault and there was a strong consensus that the bombs should be used; it was seen as a solution that would end the conflict without sacrificing further American lives.

Dan talks to Hirata San, a survivor of the Hiroshima attacks, and one of the few remaining survivors who speak English, about the Hiroshima bombing.
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Critics of the decision, however, have pointed out that Japan was on the cusp of defeat anyway and that naval blockades and conventional bombing would have forced it to surrender without the need for such a devastating assault.

Even Stimson, Truman’s secretary of war, has commented that “Japan had no allies; its navy was almost destroyed; its islands were under a naval blockade; and its cities were undergoing concentrated air attacks”.

Some historians also suggest that the bombings weren’t even the principle reason for Japan’s eventual surrender, asserting instead that the Soviet Union’s declaration of war on August 8 was the overriding factor. Exactly which factor set Japan’s eventual surrender in motion will remain much debated by historians, but whether it was the Soviet Union, the American atomic bombs, or a combination of both, Japan did eventually surrender to Allied forces on 15 August 1945.

Harry Atkins