By Dr. Stephen Schwalbe
Faculty Member, Public Administration at American Military University
As we recognize the 75th anniversary of Japan’s bombing of Pearl Harbor this Wednesday, it is a good time to review President Truman’s strategic reasoning for authorizing the deployment of two atomic bombs on the Japanese cities of Hiroshima and Nagasaki. The attacks occurred on August 6 and 9, 1945, and immediately killed more than 130,000 Japanese citizens. Tens of thousands more died later from radiation poisoning.
Most Americans today believe that using the atomic bombs saved the lives of over 1 million U.S. servicemen by eliminating the need to invade Japan’s homeland islands. “Operation Downfall” was the Allied code name for the plan to invade Japan at the end of 1945. Operation Downfall would have begun with Kyushu, Japan’s southernmost island, and moved up to the island of Honshu where Tokyo is located.
The invasion would have entailed the largest amphibious landing in history, surpassing Operation Overlord, the June 1944 D-Day landing in Normandy, France. The U.S. military estimated that almost 2 million men would have been killed as a result of the Japan invasion.
While the government justified the use of the bombs as a means of saving the lives of American service members, there was a strategic reason for using these new weapons. But, most Americans are not aware of it.
Soviets Create Western Front in Japan-Controlled China
At both the Tehran Conference in November 1943 and the Yalta Conference in February 1945, the Allies appealed to Soviet Politburo General Secretary Joseph Stalin to open a western front against Japan in the Far East. He agreed to do so exactly three months after Germany surrendered in Europe, which occurred on May 8, 1945.
However, Stalin wanted compensation for violating the Soviet-Japanese Neutrality Pact of 1941, in the form of expanding the Soviet empire. But, the Allies agreed that the Soviet Union could take back only the southern part of Sakhalin Island, which it lost in its war with Japan in 1904-05.
As the summer of 1945 arrived, the war against Japan was going better than expected. The Allies no longer needed the Soviets to attack Japan in China.
However, the deal was already signed and sealed. The Soviets promised their attack on Manchuria would begin on August 8, no matter what happened.
US Realizes Danger of Allowing Soviet Army to Invade China
By the end of the war, Japan had effectively seized control of the developed part of China — most of the East Coast provinces. At that point, U.S. leaders realized that they had to get Japan to surrender unconditionally before the Soviet invasion began in China. If not, any territory the Soviet Red Army captured in the Far East besides Sakhalin Island could become permanently part of the Soviet Union.
Japan Shocked by Soviet Invasion of China
The first atomic bomb fell on Hiroshima on August 6, two days prior to the Soviet Union declaring war on Japan and three days before the Soviet invasion of Manchuria began. But, with all communications cut off from Hiroshima as a result of the bombing, it was difficult for Japanese Imperial Army leaders to fully comprehend what had happened.
Also, Japan did not expect any interference from the Soviet Union due to the Soviet-Japanese Neutrality Pact. Imperial Army leaders counted on the Soviet Union remaining a neutral party at a minimum and an interlocutor in its peace talks with the Allies at best.
The Red Army’s surprise invasion of China consisted of more than 1.5 million soldiers, over 27,000 artillery pieces, more than 5,500 tanks and over 3,700 aircraft.
The invasion was a total success as the Soviets routed the Japanese forces. When reports of the invasion got back to the Imperial Army leadership, they were stunned. It was at this point that Japanese military leaders knew the war was over.
However, the U.S. military leadership was not aware of the change in attitude of Japan’s military leaders. Because there was still no surrender at the time and time was precious, the U.S. dropped a second atomic bomb on Nagasaki on August 9. Japan’s unconditional surrender was announced on August 15.
Soviets Reclaim Some Japanese Islands and Violate Agreement
Unknown to the Americans, the Soviets had planned also to invade Hokkaido, Japan’s northern island, and the Kurile Islands in August 1945. While the Soviet invasion of Hokkaido did not take place, the invasion of the Kurile Islands went ahead anyway, after Japan had surrendered.
While the Japanese put up valiant resistance, they eventually lost the battle and the Soviets claimed the islands for the Soviet Union.
To this day, the Allies do not recognize the Kurile Islands as part of Russia. However, these islands are the only secure ingress and egress for the Russian Navy’s Pacific fleet (particularly for its submarines), headquartered in Vladivostok.
Without the use of the atomic bombs on Japan, the Imperial Army might have held out a bit longer. That resistance would have allowed the Soviet Union enough time to invade the island of Hokkaido.
If the Soviets had managed to invade Hokkaido, Japan would have been a divided country after World War II, with all the resulting complications.
That is the strategic reason behind the use of atomic bombs against Japan in World War II.
About the Author
Dr. Stephen Schwalbe is an associate professor at American Military University. He is also an adjunct professor at Columbia College and Embry-Riddle Aeronautical University. Stephen received a Ph.D. in Public Administration and Public Policy from Auburn University in 2006. His book about military base closures was published in 2009.