The sky was blue on the morning of August 6, 1945 when, suddenly, there was a blinding, searing flash of light, which cast a bluish haze over everything in sight. That was followed by a thunderous, earsplitting blast that shook the earth, and seemed to penetrate to the marrow of my bones.

An immense fireball crackled as it burned. Hellish orange flames raged, and a pillar of fire rose to the skies with terrifying momentum. It was an atomic bomb, and it claimed hundreds of thousands of precious lives.

– Yasuhiko Taketa, survivor of the Hiroshima bombing

This week marks the 70th anniversary of the first use of a nuclear bomb as a weapon of warfare. However, a debate still goes on over whether the attacks on Hiroshima, and later Nagasaki, were justifiable or if they can be considered as a war crime. I take a closer look at the arguments…

 As J. Samuel Walker said: “the fundamental issue that has divided scholars over a period of decades is whether the use of the bomb was necessary to achieve victory in the Pacific on terms satisfactory to the United States.”

Supporters argue that the bombing of Hiroshima, and of Nagasaki three days later, caused the Japanese surrender which helped prevent much larger casualties on both sides in a planned invasion of Japan, codenamed Operation Downfall. U.S. military planners believed that an invasion would inevitably result in high casualties, with some estimating that one million American troops could be killed or injured. Moreover, they argue that the atomic bombings prevented the deaths of some ten million people as a result of Operation Starvation and liberated millions more working in harsh conditions under forced mobilisation.

However, there are many who dispute this, characterising the bombings as war crimes and crimes against humanity. Those who opposed the use of nuclear weapons on the two cities argue that, despite the war crimes committed by the Empire of Japan, the U.S. violated internally accepted principles of war with respect to the wholesale destruction of populations. Historians, such as Gar Alperovitz, argue that the military leadership of the United States knew that the bombs were unnecessary, because in all probability Japan would have surrendered regardless. This sentiment is echoed by William D. Leahy, Chief of Staff to both President Roosevelt and President Truman. In his 1950 memoir ‘I Was There’ he said:

It is my opinion that the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender because of the effective sea blockade and the successful bombing with conventional weapons.

In addition, opponents point to the Hague Convention of 1907, specifically the Convention respecting the Laws and Customs of War on Land, which stated:


“The attack or bombardment, by whatever means, of towns, villages, dwellings, or buildings which are undefended is prohibited.”


“In sieges and bombardments, all necessary steps must be taken to spare, as far as possible, buildings dedicated to religion, art, science, or charitable purposes, historic monuments, hospitals, and places where the sick and wounded are collected, provided they are not being used at the time for military purposes.”

This would suggest, at least on first glance, that the atomic bombings amounted to a war crime. That said, those who supported the decision would argue that the nature of the Second World War as a ‘total war’ meant that any means necessary could and should be used to achieve victory. As well as this, given the level of technology and accuracy of aerial bombardment at time, it could be argued that it was impossible to guarantee the protection of civilian buildings when attacking military targets nearby.

The debate over the morality and legality over the attacks will, inevitably, continue for many years to come. To this day no international treaty banning or condemning nuclear warfare has ever been ratified.