Japanese soldiers surrendering their weapons to Soviet Army, northeastern China, Aug 1945. Source: US LIbrary of Congress
The United States dropped two nuclear bombs on Japan, a third, according to Brigadier General Leslie Groves, the director of the Manhattan Project, could have been ready for delivery by August 17 or 18, and a fourth by September 1945. But the American military command never canceled its training exercises for Operation Downfall – the ground invasion of the Japanese islands.
How many Japanese cities would have eventually been incinerated by the Americans if, over the course of 12 days (Aug. 9-20, 1945) in Manchuria, the Soviet Union had not wiped out the Kwantung Army, the biggest command within the Japanese army, with over one million troops, and thus forced the surrender of Emperor Hirohito?
Little already remained of Tokyo long before the attacks on Hiroshima and Nagasaki. If the intent was to destroy tactical targets (and Hiroshima was one of the largest military centers provisioning the Japanese army and navy), would it not have been better to have gone about it using conventional weapons?
The fact that Nagasaki was a haphazard target (the plane originally flew to Kokura, but because of cloud cover it was unable to release its payload and it turned toward Nagasaki instead), the nuclear bombings on Japan were conducted with a purely terrorist purpose.
Originally the chosen targets for the attack were Niigata (a military base and industrial center), Yokohama (an industrial center), Kokura (which held the largest arsenal and warehouse), and Kyoto (also an industrial center). Kyoto was eliminated from the “list of death” because of its historical value thanks to some American generals who used to attend it before the war.
It took Emperor Hirohito and his war cabinet a long time to obtain a reliable assessment of the scale of the incident and to make a political decision based on the aftermath of the first bombing. Tokyo only learned about the use of these previously unknown weapons of mass destruction thanks to American radio broadcasts. The emperor was far more concerned about the attitude of Soviet Union regarding the war in the Far East.
The emperor was ready to surrender back in May 1945, but not unconditionally like Germans. He wanted an honorable surrender that would safeguard his regime (what subsequently happened) and army. His trump card in the political bartering was the existence of the still viable Kwantung Army. This, and not the mythical “hundreds of thousands of kamikaze pilots,” posed the biggest threat to the Allies.
If the Kwantung Army had not suffered a crushing defeat Japan could have held out a few more months. But the Allies would have found themselves embroiled in massive operations on mainland China, something for which the US was not ready.
The USSR’s entry into the war against Japan on Aug. 9, 1945 had a decisive impact on Japan’s decision to capitulate. That same day, Japan’s prime minister, Kantarō Suzuki, declared at the meeting of Supreme Military Council:
…the entry of the Soviet Union into the war this morning puts us in a completely helpless position and makes continuation of the war impossible…
Four days later, when the fate of the Kwantung command was almost a foregone conclusion, Emperor Hirohito decided to surrender. So what most affected his decision – the panicked reports from his military commanders in Manchuria or an American radio broadcast?
Neither President Truman, the US military, nor the rest of the world fundamentally grasped the consequences of the atomic bombardment. Of course, the scientists who created the bomb could theoretically imagine what its effect might be.
But the practical aspects behind the use of nuclear weapons, as well as the basic principles for how they were to be managed, developed only after seeing the impact of the bombing of Hiroshima and Nagasaki. Only then did an understanding evolve of the mechanism behind the spread of the shock-, light-, heat-, and electron waves, and only then did it become possible to forecast the damage by studying the landscape and weather.
Effects of radiation were studied years later, based on observations of the “hibakusha” – the more than 200,000 people who were afflicted by the fallout. So is it possible that at that time the US was simply tempted to conduct an experiment on the civilian population of its wartime opponent, merely in order to make some adjustments to its scientific records?
There are no real reasons to believe that if the war had continued with the use of conventional weapons this would have resulted in the
catastrophic level of casualties that were predicted by the US General Staff and President Truman.
Only on two islands – Saipan and Okinawa – did the Japanese offer their most fierce and fanatical resistance. Of course, the mind-boggling kamikaze deaths remained a perplexing headache for America’s pragmatic admirals. However, the rapid annihilation of the Kwantung Army, as well as the Soviets’ amphibious operations in Korea and the Kuril Islands (these landings differed little from those conducted during America’s offensive operations, but were better organized), proved that notorious “Japanese morale” had already dissipated.
So, who was Washington intending to intimidate – the demoralized Japanese or its future opponent in the Cold War, i.e. the Soviet Union?