Hell to Pay

30 Jul 18
Posted by: Tim Coyle

by D.M. Giangreco

Hell to Pay: Operation Downfall presents, in definitive detail, the strategic, operational and tactical challenges faced by US forces in planning and carrying out Operations OLYMPIC – the invasion of the southernmost Japanese homeland island of Kyushu – and CORONET, the invasion of Honshu. It starkly depicts the awesome potential for disaster facing invading forces which, while likely prevailing in the longer term, would have strained US capability to, and perhaps beyond its limits, were the nuclear option not exercised in August 1945. This 2017 edition is an updated version of the 2009 original with additional chapters, research, new archival material, new maps and more photographs.
As a treatise on the planning and build-up of ‘conventional’ forces to mount an invasion of the Japanese homeland’ the book barely mentions the atomic weapon development and the decision to use it. The underlying message is that were the atomic attacks not carried out US forces would have suffered one million dead or wounded; Japanese deaths were conservatively estimated to be from three to five million.
D.M. Giangreco has published extensively on military studies topics and is a past editor of the US Army Command and Staff College Military Review and Director at the Foreign Military Studies Office. His depth of scholarship in analysing primary and secondary sources, including the G-2 (Intelligence) Estimates of the Enemy Situation on Kyushu and the Analysis of Japanese Planes for the Defense of Kyushu (provided as annexes in the book) underpin the value of this work.
Despite the almost total destruction of the Imperial Japanese Navy and the Japan’s mercantile marine, millions of men were available to contest the sacred soil of the homeland, supported by practically the entire Japanese civil society. US commanders were under no illusion; this from Major General Graves B. Erskine, commanding general, 3rd Marine Division: “Victory was never in doubt. Its cost was…What was in doubt, in all our minds, was whether there would be any of us left to dedicate our cemetery at the end, or whether the last Marine would die knocking out the last Japanese gun and gunner.”
Setting the scene for the manning of the invasion forces, Giangreco provides a chapter on casualty analysis up to the early months of 1945. US forces lost 65,000 men per month during the ‘casualty surge’ which followed Operation OVERLORD for a total of 664,000 casualties. This chapter is very detailed but it shows that a continuous supply of men were required for ‘Selective Service’ –100,000 per month – for the build-up to Operation DOWNFALL. Exacerbating this, over and above the casualties, was the need to discharge veterans who had seen action in Europe. This requirement, plus the publication of casualty figures, began to affect home front morale. Given the US casualty count at Okinawa, where US troops had to fight hand to hand after days of naval and air bombardment prior to landing, the country was being steeled for much more of the same horrific combat.
Operation OLYMPIC was scheduled to start on 1 September 1945. After securing beachheads and moving inland US forces would establish airfields and bases in the southern half of Kyushu thence move north to take the whole island. Operation CORONET, the invasion of Honshu and the Kanto Plain, which included Tokyo, was planned for March 1946 and expectations were that the war would continue into 1947, or indeed longer.
In April 1945 Japan realised that invasion was imminent and reorganised its defence forces the basis of which were seven geographically-specific ‘Ketsu-Go’ operations. Ketsu-Go 6 was the defence of Kyushu by the Sixteenth Area Army. Kyushu was a certain target and its fortification was of the highest urgency and of equal priority to Ketsu-Go 3 which was defence of the Kanto Plain including Tokyo and the imperial palace. The Japanese had ample to time fortify their positions and stockpile ammunition and supplies not only for Ketsu-Go 6 but, as the Japanese correctly assessed that Operation Coronet would not launch until Kyushu had been subjugated, Ketsu-Go 3 would be even more prepared. The book provides detailed maps of Japanese dispositions for both Ketsu-Go operations and the Operations OLYMPIC and CORONET assault plans with supporting analysis.
By this time the US Navy was well acquainted with kamikaze tactics and invading forces fully expected to be met off the beaches by suicide boats, human torpedoes and aircraft. US intelligence on the Japanese air order of battle underestimated the number of aircraft available for suicide attacks. The majority of the kamikazes met with had been regular military aircraft; however in July 1945 aviation training units were converted into combat formations adding 5400 wood-and-fabric trainers and other second-line aircraft into a formidable threat based on these aircraft invulnerability to radar and to the much vaunted US VT ‘proximity’ fuses. Two successful attacks against US destroyers by these aircraft which were undetected in July confirmed the effectiveness of this asymmetric weapon. Adding many hundreds of small suicide surface craft and midget submarines off Kyushu led US intelligence to assess a 50 percent loss rate of amphibious transports as they positioned to disembark troops into landing craft committed to a complex choreography of forming up before assaulting the beach. Okinawa, Iwo Jima and Tarawa had shown that despite naval and air bombardments over days, assaulting troops had to fight hand to hand against fanatical Japanese defenders.
The G-2 analysis starkly describes the extremely difficult terrain with which invading forces would have to contend. The Kyushu beaches featured rows of serrated ground, almost small cliffs. Kyushu and Honshu interiors comprised highly defensible terraced rice fields which could not be bypassed; waterlogged so as to impede wheeled and armoured vehicles. Primitive roads, susceptible to collapse under vast numbers of heavy vehicles, added to the invaders’ movement problems.
The book includes the two annexes mentioned above and Operation BLACKLIST, the Occupation of Japan, part of the Reports of General MacArthur dated 1950 and edited by Major-General Willoughby, MacArthur’s intelligence chief. The report describes the dramatic, almost surreal, sequences of the Japan’s surrender and its subsequent occupation. The transformation of the Japanese military and indeed the whole of society from a full expectation of national annihilation to meek and cooperative acquiescence, indeed welcoming the occupation forces, which took place over a few days continues to amaze after 73 years. Again the almost unspoken theme of the atomic attacks does not feature but this book proves that the US and its allies would have suffered enormous casualties were that option not taken.
This is an important work. While it challenges the moralistic issue of the atomic bomb this emotive topic may be gradually fading from contemporary conversation. Of greater weight is the military implications of invasion which are as relevant now as they were 70 plus years ago. Japan was exceptional in that the nuclear weapon caused its surrender and the subsequent peaceful acquiescence. However, since then we have had Korea, Vietnam, Iraq and Afghanistan. The presence of foreign troops in benighted countries, for whatever ostensibly good reason, has been at the very least problematical and of great cost to ‘blood and treasure’. Current touting of a ‘ground invasion’ of a north-east Asian country may find the population as prepared to fight to the death as the Japanese despite the odiousness of the regime.

Tim Coyle
Australian Naval Institute