Avoidable Slaughter or Radiation: The Allied Dilemma of the Atomic Bomb and the Invasion of Japan
The Allied Pacific Command in May of 1945 was faced with an enormous quandary. Japanese territories had effectively shrunk to just Manchuria, Korea, Taiwan, and the Home Islands; President Franklin D. Roosevelt had died just a month earlier, and the Soviets gave no indication on when they would enter the war against Japanese forces in China. However, Japan refused to surrender. This forced the decision of how to proceed onto Allied High Command: invade Japan, engineer a rice famine, drop the newly-proven atomic bomb, or a combination of all three options. All three were horrible options, and yet one had to be chosen. The American public was tired of war, and manpower reserves were dwindling. Ultimately, the atomic bomb was chosen, and the Soviets invaded Manchuria, both contributing to the Japanese surrender. Although the three options for ending the war were terrible, the atomic bombings of Hiroshima and Nagasaki were less fatal than a proposed invasion of Japan, and thus prevented an entirely avoidable mass killing of Japanese civilians.
The first proposed option to end the war quickly was to engineer a famine in the 1946 rice crop, with the TN8 herbicide. This option was made without the knowledge of the extant collapse of the 1945 rice crop, exacerbated by the deficient state of the Japanese rail system. Even though the war ended in 1945 before a massive famine could start, “the extremely diminished rice supply available for the period through to November 1946, generated a massive depopulation of Japan’s urban centers.” If the rail system was destroyed, however, over half of Japan’s 72 million souls would have been affected by the famine. Japan’s more traditional coastal transit system had by this time been destroyed and could not supplement the rice crop’s transport needs. This would have had a major impact on postwar Japanese development, potentially even contributing to the inability of the population of the Japanese Home Islands to maintain a functioning society due to mass depopulation. If this collapse had happened, the historical Japanese culture that had existed since 660 B.C.E. likely would have been lost entirely.
The second proposed option of defeating Japan was codenamed Operation Downfall, the invasion of Kyushu, the southernmost Japanese Home Island. The plan would “bring about the unconditional surrender of Japan within 18 months of the defeat of Germany” and “require 1,700,000 U.S. troops” in order to avoid the consequences of war fatigue. It was unknown if the U.S. could keep up with the anticipated carnage that would be the invasion, as U.S. casualties were already at horrific rates in previous engagements at Okinawa, Saipan, and Iwo Jima. More would have been politically unacceptable and logistically almost impossible to replace from the dwindling manpower reserves in the continental U.S., United Kingdom, Australia, and other Allied homelands. For these reasons, the U.S. Army and Navy were heavily reluctant to commit to this plan of attack. Unknown to the Allied High Command, however, Japan’s Imperial General Headquarters had anticipated where and when Allied troops would theoretically land, and planned accordingly for the landing. This final defensive strategy - Operation Ketsu-Go - was planned “to actively defend the few selected beach areas at the beach, and then to mass reserves for an all-out counterattack if the invasion forces succeeded in winning a beachhead.” To do this, not only were all the remaining forces in the area were reinforced according to principles learned from previous engagements with the Americans and other Allied forces, suicide forces heavily ramped up production, and the remains of the Imperial Japanese Navy and Air Forces gathered to Kyushu and other invasion sites, but also created what was termed the Civilian Volunteer Corps (CVC). The CVC would have mobilised “all boys and men 15 to 60 and all girls and women 17 to 40,” armed them with any weapon available (ranging from swords to hand grenades and bamboo spears), and sent to infiltrate American positions at night and kill anyone they found.
Not only would Allied forces face constant suicide attacks from suicide motorboats, human torpedoes, bayonet charges, and bomb-laden biplanes (among other forms), but the occupation troops would also face the uncertainty of not knowing whether the next civilian would attack them or ask for food. The projected casualties of invasion were, conservatively, 1.7 to 4 million U.S. casualties (400,000 to 800,000 deaths), and 5 to 10 million Japanese deaths. The population loss from either would have fatally undermined the reconstruction of any Japanese state, and contributed towards what would have been an avoidable mass killing of Japanese civilians.
The third option, and ultimately the path taken, was to drop the atomic bomb on Hiroshima and Nagasaki. The atomic bombs were dropped on the 6 and 9th of August, and contributed significantly towards the surrender in 1945. The casualties from the bomb are unclear; the low end estimates from the Bulletin of Atomic Scientists range from 110,00 (70,000 in Hiroshima and 40,000 in Nagasaki) to 210,000 (140,000 at Hiroshima and 70,000 in Nagasaki). This includes both immediate deaths from the initial blasts, and deaths from radiation sickness and other diseases associated with nuclear detonations. Though they could have been used more effectively, and despite their high death toll, the bombings were undoubtedly less fatal than the other options. This also allowed Japan to surrender more easily and preserve the lives of Japanese civilians, and their post-war nationhood.
The dropping of the atomic bomb, as horrific as its immediate and long-term effects were, was not the worst option that could have been pursued in the fight to force a Japanese surrender. Engineering a famine and invasion were on the table, as was a combination of atomic bombings and invasion. Japan was very adamant in resisting surrender, until the bombings and Soviet invasion of Manchuria. Civilians would have been conscripted in the event of an invasion, and engineering a famine would have lost all of the moral high ground gained from the attack on Pearl Harbour. Thus, as terrible as the effects were, the atomic bombs prevented the mass killing of Japanese civilians and collapse of Japanese nationhood.
Image description: Map showing the Second World War’s Pacific theatre of operations, 1941–1945. The dark line marks the high tide of Japanese expansion across the Pacific in July 1942.
Image courtesy of New Zealand Government via NZ History, ©2000. Some rights reserved.
The views and opinions expressed in this article are those of the author and do not necessarily reflect those of the wider St. Andrews Foreign Affairs Review team.
