Counterfactual history has in recent years become an increasingly popular area of historical study with numerous books having been released over the last few years. These books have been produced by well known authors such as Robert Cowley, Niall Ferguson, Erik Durschmied and Dennis Showalter. Counterfactual history offers the historian a unique tool into why some decision were made and why other were not and as Robert Fogel has noted ‘…counterfactual propositions are implicit in many historical judgements…’ Thus, counterfactuals offer the historian insights into what might have been had the chosen course not been selected.
One of the greatest counterfactuals in military history and also the history of the twentieth century is President Truman’s decision in 1945 to order the deployment and use of the atomic bombs on the Japanese cities of Hiroshima and Nagasaki. The question of what if the bomb had not been used it offers several counterfactuals for the subsequent course and development of the war. There are several possibilities, which could be investigated with this counterfactual. Firstly, there is the planned US invasion of the Japanese home islands, Operation DOWNFALL. Secondly, the outcome of the continued strategic bombing campaign and maritime blockade of the home islands, which is cited by the United States Strategic Bombing Survey (USSBS) as being able to win the war without the use of the atomic bombs. Thirdly, there is the Soviet card, whom entered the war against Japan on 9 August 1945, and their planned operations in Manchuria and in Korea, an operation which Hatano Sumio comments ‘…had a greater effect on the decision by Japanese leaders to end the Pacific war…than the…atomic bombs…’ Finally, there is one aspect which is often forgotten about when thinking about the end of the war in the Far East and that is British and Commonwealth operations in the vital theatre of South-East Asia, an area that would become a melting pot in the immediate post war period, especially French-Indochina.
The first area of this What If to be considered is the planned US invasion of the Japanese home islands. Operation DOWNFALL was planned to go ahead in two distinct phases. The first phase was to be Operation OLYMPIC, the invasion and occupation of the Japanese islands of Kyushu. This operation was to be launched on November 1 1945. After this Operation CORONET, was to land larger invasion forces on the Kanto plain of Honshu and occupy Japan’s political and industrial heartland of Tokyo and Yokohama. CORONET was to be launched in March 1946. The planned forces for the operation were to be massive in size. OLYMPIC would be larger than the invasion of Europe, OVERLORD, and CORONET would be larger still. In terms of lands forces there would be four distinct armies involved in both operations. These were the Sixth, Eight and Tenth armies which were already in Pacific Theatre of Operations (PTO) and the First army, which was due to be redeployed from the European Theatre of Operations (ETO). In total there would be somewhere in the region of five million men involved in DOWNFALL. The vast majority of these forces would be American, though Britain and the Commonwealth would be contributing a small force of three divisions, one each from Britain, Canada and Australia, the British Pacific Fleet, then serving with Admiral Halsey’s Fifth Fleet and some squadrons from the Royal Air Force. This was a massive force with a single purpose, the occupation and subjugation of the Japanese home islands. As paragraph one of the Strategic plans for DOWNFALL comments the ‘…Strategic Plan constitutes the basis for directives for operations to force the unconditional surrender of JAPAN by seizure of vital objectives in the Japanese Archipelago.’
While American plans for DOWNFALL continued the Japanese too planned for a possible invasion of their home islands. Their counter operation for American incursion of their home islands was codenamed Operation KETSU – GO. The plan called for massive strikes against the invading forces. It has for many years been estimated that by 1945 Japanese forces and industry were on the verge of complete and utter destruction, and while this is to some extent true, the Japanese army itself was able to mobilise a vast amount of men and material to meet any invasion of the home islands. The Japanese army was able to amass nearly two and a half million men organised into fifty three infantry divisions and twenty five brigades. On top of this there were two armoured division, seven armoured brigades and four anti-aircraft divisions. A not too inconsequential force with which to repel the invaders. They were organised into four area armies to guard the home islands. In addition to this there were approximately twenty eight million men in the National Volunteer Force, a Home Guard of sorts. In addition there were numerous Kamikaze units ready to repel the invaders. It is approximated that the Kamikaze forces had amassed somewhere in the region of five thousand aircraft and one thousand suicide craft with which to barrage the invasion fleets anchored of the islands of Japan. It was these forces that would have created the greatest worry for the invading forces.
US estimates of casualties for the invasion of Japan were based on their preceding campaigns on the islands of Iwo Jima and Okinawa and the recapture of the Philippines. For example, during the campaign for Okinawa US forces had suffered heavily. There were 7613 soldiers killed and 31,807 wounded. This works out as a casualty rate of approximately twenty three percent of the forces committed to the battle. The naval forces involved also suffered heavily losing thirty six warships. Based on these casualties it was estimated by some in the US War Office that in the initial invasion period the Americans would lose somewhere in the region of half a million men killed and wounded. However, it is possible that it may not have been this high because the closer US forces got to Japan the more the war took its toll on the Japanese military. The Japanese military ethos on the eve of World War II related to honour and obedience and fighting, literally, to the last soldier. For example, during the fighting for Tarawa in 1943 only one hundred and forty six Imperial Japanese Marines surrendered out of a force four and a half thousand. However, this ethos had changed by the time of the assault on Okinawa when as many as seven thousand men surrendered. As such the Japanese militaries combat efficiency had declined; therefore, it could be argued that by the time of DOWNFALL Japanese resistance would not have been what it was during the early campaigns of the Pacific war. Thus, an invasion of Japan may well have been easier than had been previously thought, though on the other hand it may have been just as bloody as predicted.
However, it may never have had to come to invasion due to the second what if. After the capture of the Marianas in 1944, the last island, Guam, fell in August of that year, US strategic bombers came into effective range of the Japanese home islands and could launch an air war with which to disrupt Japan’s war production and command and control networks. The reduction of Japan was left the US 20th Army Air Force, which operated off the island of Tinian in the Marianas. When the USSBS reported its findings it claimed that Japan would have surrendered by November 1945, the projected date for Operation OLYMPIC, from the weight of the strategic bombing campaign. As the USSBS comments, ‘Based on a detailed investigation of all the facts, and supported by the testimony of the surviving Japanese leaders involved, it is the Survey’s opinion that certainly prior to 31 December 1945, and in all probability prior to 1 November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated.’
The report argued that if the bombing of Japan’s cities and industrial targets had continued then she would have had to of surrendered by late 1945. The conventional strategic bombing campaign is best typified by the fire bombing of Tokyo. The raid, launched on the 9/10 March 1945, caused massive damage to Tokyo’s infrastructure destroying up to twenty industrial targets and causing up to eighty five thousand Japanese casualties. The continuation of the firebombing campaign coupled with the US Navy’s blockade of Japan’s important sea lanes through the use of submarine warfare caused the crippling of Japan’s ability to continue the war. America’s strategic bombing force in the Pacific would have been, by the latter part of 1945, significantly reinforced by units from the ETO. It was planned the US 8th Air Force with it Boeing B17’s Flying Fortresses would redeploy to the PTO. This would add approximately two thousand airframes to the already significant force of Boeing B29 Superfortresses of the 20th Air Force. The Royal Air Force also planned to deploy three bomber groups to the Far Eat under the auspicious of ‘Tiger Force’ This force would have been equipped with Avro Lancaster MkX and the new Avro Lincoln, both long range bombers with significant payload capacity’s. Had this campaign been allowed to continue with all of its added weight it would have arguably brought Japan to its knees without the use of the atomic bombs or the need for an invasion. As Robert Paper has argued in Bombing to Win: Air Power and Coercion in War the strategic bombing campaign against the Japanese was the most successful case of military coercion through the use of air power and even without the atomic bombs its still stands out as an immensely successful campaign.
Another aspect of the alternative decisions for the end of World War II is the role of the Soviet Union in the Far East. It had been a constant in allied planning that the Soviet Union would enter the war against Japan. At the Yalta Conference, ARGONAUT, in February 1945 it was agreed that in return for Soviet entry against Japan there would be status quo in Mongolia and the acquisition of Sakhalin and the Kurile Islands. With this agreement and the end of the war in Europe, Soviet units were gradually transferred to the Far East via the trans-Siberian railway. In the space of two months Marshal Vasilevsky’s Far Eastern Command had doubled from forty to eighty divisions and on 9 August the Soviet’s launched a massive assault on the Japanese Kwantung army based in Manchuria. By the end of hostilities on and about August 20 the Red Army had destroyed the Kwantung army causing more than 80,000 casualties. This operation was but a precursor for what had been planned by the Soviets. They had planned a continued advance into Korea and an invasion of the Japanese home island of Hokkaido at about the same time as the first US planned invasion, Operation OLYMPIC, in November 1945. If this planned invasion had gone ahead it may well have had huge effects on the post-war nature of Japan and the Far East. It can easily be surmised that Japan would have been occupied in a similar manner a Germany was with three zones of occupation, US, Britain/Commonwealth and Soviet, rather than just being occupied by America. Tokyo would, therefore, had become the Berlin of the Far East but in the Allied zone rather than Soviet zone as Berlin was. It would have, therefore, been a useful counterweight to Soviet demands over the status of Berlin in 1948. As such it can be seen that while Soviet entry would have helped in the destruction and downfall of Japan it may well have added another aspect to the Cold War with Japan becoming America’s counterweight to Soviet power in central Europe. However, it must also be kept in mind that with Stalin having a say in Japanese politics there may well have been a shift in American post – war policy in the Pacific too. This was because in both the Korean War and the Vietnam War, Japan was used as a logistics springboard with which to launch their campaigns.
While the actual fate of Japan has been considered by many historians with respect to the use of the atomic bomb and any other possible alternatives, one area which has often been left out of these considerations is the fate of South East Asia in the final months of the war. With the launch of Operations CAPITAL and DRACULA, Field Marshal the Viscount Slim, commander of the British 14th Army and subsequently land commander for South East Asia, launched the liberation of Burma. DRACULA was the culmination of many years of hard fighting and saw the re-capture of Rangoon. With this act Burma was liberated and planning was underway for the liberation of all former British colonies in the region. The British had planned to send forces from Germany to Burma in order to facilitate further advances and in preparation General Stopford formed the 12th Army which would eventually be handed over to General Sir Miles Dempsey, former commander of the 2nd Army in North West Europe. Under this command structure, headed by Slim, who was by now Allied Land Force Commander South East Asia, the British/Commonwealth forces had planned the liberation of Malaya, Operation ZIPPER, Sumatra, Operation CULVERIN and the capture of the Andaman Islands, Operation BUCCANEER. This combined with the Australians coming up from Borneo was designed to clear the Japanese from all colonial possessions. Had the war continued and Britain ‘liberated’ these countries the communist insurgent forces which had resisted the Japanese and then turned against the British post war may not have been able to draw on the popular support which they did after the war. If this had occurred Britain’s position in South East Asia may well have been much stronger and any subsequent retreat from the Empire may well have been far less bloody and these countries transition to democracy may well have been smoother.
While in the British colonies this may have been possible, French colonies would have been a much greater problem as they had no forces in the region, the first French troops did not arrive until December 1945, thus it may have been harder to assume a position of the liberator without the support of Britain. Though this may have been true, the crumbling of Japanese resistance may have seen increased pressure from the Viet Minh and Chinese Communist forces and such given them a much stronger position against the French colonial administrators when or if they returned. This may well have led to a united Vietnam thirty year earlier and without the bloodshed of two subsequent wars.
In conclusion it can be seen that there are many what ifs concerning the ending of the war in pacific, many of them involve important decisions on the state of the post war world in the Far East and South East Asia. For example, if the Soviet Union had invaded Japan would it have become a powder keg like Berlin was in Europe or would it become a counterweight to Stalin policies in Europe. A vast amount of literature has been written on the subject, a vast amount of it dealing with the planned US invasion, this has stemmed from an attempt to explain the eventual use of the atomic bomb and whether it was morally right to use it when there were other alternatives to the planner of the war but had they been used would the war have been better of than if the bomb was used. That is an argument that will undoubtedly go on as we do not know as that is the point of a counterfactual, we are surmising on event that did not happen and as Richad Franck has noted because of the prevailing Soviet posture, the ‘war had to end when it did’, which may well have been best for all involved.