The US Plan for the 1945 Invasion of Japan

[AJChenMPH]

This is a loooooooong but interesting read. Without double-checking the references on Wikipedia's page on Operation Downfall, this appears to be an accurate account and analysis of what would have happened. This brings up two points in my mind:
- Truman was right: the atomic bombs dropped on Hiroshima and Nagasaki did save a lot of lives.
- The Japanese were damned good at following most (if not all) of Sun-Tzu's principles.

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Deep in the recesses of the National Archives in Washington, D.C., hidden for nearly four decades lie thousands of pages of yellowing and dusty documents stamped "Top Secret". These documents, now declassified, are the plans for Operation Downfall, the invasion of Japan during World War II. Only a few Americans in 1945 were aware of the elaborate plans that had been prepared for the Allied Invasion of the Japanese home islands. Even fewer today are aware of the defenses the Japanese had prepared to counter the invasion had it been launched.

Operation Downfall was finalized during the spring and summer of 1945. It called for two massive military undertakings to be carried out in succession and aimed at the heart of the Japanese Empire.

In the first invasion - code named "Operation Olympic"- American combat troops would land on Japan by amphibious assault during the early morning hours of November 1, 1945 - 61 years ago. Fourteen combat divisions of soldiers and Marines would land on heavily fortified and defended Kyushu, the southernmost of the Japanese home islands, after an unprecedented naval and aerial bombardment.

The second invasion on March 1, 1946 - code named "Operation Coronet"- would send at least 22 divisions against 1 million Japanese defenders on the main island of Honshu and the Tokyo Plain. It's goal: the unconditional surrender of Japan. With the exception of a part of the British Pacific Fleet, Operation Downfall was to be a strictly American operation. It called for using the entire Marine Corps, the entire Pacific Navy, elements of the 7th Army Air Force, the 8 Air Force (recently redeployed from Europe), 10th Air Force and the American Far Eastern Air Force. More than 1.5 million combat soldiers, with 3 million more in support or more than 40% of all servicemen still in uniform in 1945 - would be directly involved in the two amphibious assaults.
Casualties were expected to be extremely heavy.

Admiral William Leahy estimated that there would be more than 250,000 Americans killed or wounded on Kyushu alone. General Charles Willoughby, chief of intelligence for General Douglas MacArthur, the Supreme Commander of the Southwest Pacific, estimated American casualties would be one million men by the Fall of 1946. Willoughby's own intelligence staff considered this to be a conservative estimate.

During the summer of 1945, America had little time to prepare for such an endeavor, but top military leaders were in almost unanimous agreement that an invasion was necessary. While naval blockade and strategic bombing of Japan was considered to be useful, General MacArthur, for instance, did not believe a blockade would bring about an unconditional surrender. The advocates for invasion agreed that while a naval blockade chokes, it does not kill; and though strategic bombing might destroy cities, it leaves whole armies intact.

So on May 25, 1945, the Joint Chiefs of Staff, after extensive deliberation, issued to General MacArthur, Admiral Chester Nimitz, and Army Air Force General Henry Arnold, the top secret directive to proceed with the invasion of Kyushu. The target date was after the typhoon season.

President Truman approved the plans for the invasions July 24. Two days later, the United Nations issued the Potsdam Proclamation, which called upon Japan to surrender unconditionally or face total destruction. Three days later, the Japanese governmental news agency broadcast to the world that Japan would ignore the proclamation and would refuse to surrender. During this same period it was learned -- via monitoring Japanese radio broadcasts -- that Japan had closed all schools and mobilized its school children, was arming its civilian population and was fortifying caves and building underground defenses.

Operation Olympic called for a four pronged assault on Kyushu. Its purpose was to seize and control the southern one-third of that island and establish naval and air bases, to tighten the naval blockade of the home islands, to destroy units of the main Japanese army and to support the later invasion of the Tokyo Plain. The preliminary invasion would began October 27 when the 40th Infantry Division would land on a series of small islands west and southwest of Kyushu. At the same time, the 158th Regimental Combat Team would invade and occupy a small island 28 miles south of Kyushu. On these islands, seaplane bases would be established and radar would be set up to provide advance air warning for the invasion fleet, to serve as fighter direction centers for the carrier-based aircraft and to provide an emergency anchorage for the invasion fleet, should things not go well on the day of the invasion.

As the invasion grew imminent, the massive firepower of the Navy - the Third and Fifth Fleets -- would approach Japan. The Third Fleet, under Admiral William "Bull" Halsey, with its big guns and naval aircraft, would provide strategic support for the operation against Honshu and Hokkaido. Halsey's fleet would be composed of battleships, heavy cruisers, destroyers, dozens of support ships and three fast carrier task groups. From these carriers, hundreds of Navy fighters, dive bombers and torpedo planes would hit targets all over the island of Honshu. The 3,000 ship Fifth Fleet, under Admiral Raymond Spruance, would carry the invasion troops.

Several days before the invasion, the battleships, heavy cruisers and destroyers would pour thousands of tons of high explosives into the target areas. They would not cease the bombardment until after the land forces had been launched. During the early morning hours of November 1, the invasion would begin. Thousands of soldiers and Marines would pour ashore on beaches all along the eastern, southeastern, southern and western coasts of Kyushu. Waves of Helldivers, Dauntless dive bombers, Avengers, Corsairs, and Hellcats from 66 aircraft carriers would bomb, rocket and strafe enemy defenses, gun emplacements and troop concentrations along the beaches.

The Eastern Assault Force consisting of the 25th, 33rd, and 41st Infantry Divisions, would land near Miyaski, at beaches called Austin, Buick, Cadillac, Chevrolet, Chrysler, and Ford, and move inland to attempt to capture the city and its nearby airfield. The Southern Assault Force, consisting of the 1st Cavalry Division, the 43rd Division and Americal Division would land inside Ariake Bay at beaches labeled DeSoto, Dusenberg, Essex, Ford, and Franklin and attempt to capture Shibushi and the city of Kanoya and its airfield.

 

[AJChenMPH]

On the western shore of Kyushu, at beaches Pontiac, Reo, Rolls Royce, Saxon, Star, Studebaker, Stutz, Winston and Zephyr, the V Amphibious Corps would land the 2nd, 3rd, and 5th Marine Divisions, sending half of its force inland to Sendai and the other half to the port city of Kagoshima.

On November 4, the Reserve Force, consisting of the 81st and 98th Infantry Divisions and the 11th Airborne Division, after feigning an attack on the island of Shikoku, would be landed -- if not needed elsewhere -- near Kaimondake, near the southernmost tip of Kagoshima Bay, at the beaches designated Locomobile, Lincoln, LaSalle, Hupmobile, Moon, Mercedes, Maxwell, Overland, Oldsmobile, Packard, and Plymouth.

Olympic was not just a plan for invasion, but for conquest and occupation as well. It was expected to take four months to achieve its objective, with the three fresh American divisions per month to be landed in support of that operation if needed. If all went well with Olympic, Coronet would be launched March 1,1946. Coronet would be twice the size of Olympic, with as many as 28 divisions landing on Honshu.

All along the coast east of Tokyo, the American 1st Army would land the 5th, 7th, 27th, 44th, 86th, and 96th Infantry Divisions, along with the 4th and 6th Marine Divisions. At Sagami Bay, just south of Tokyo, the entire 8th and 10th Armies would strike north and east to clear the long western shore of Tokyo Bay and attempt to go as far as Yokohama. The assault troops landing south of Tokyo would be the 4th, 6th, 8th, 24th, 31st, 37th, 38th, and 8th Infantry Divisions, along with the 13th and 20th Armored Divisions.

Following the initial assault, eight more divisions - the 2nd, 28th, 35th, 91st, 95th, 97th, and 104th Infantry Divisions and the 11th Airborne Division -- would be landed. If additional troops were needed, as expected, other divisions redeployed from Europe and undergoing training in the United States would be shipped to Japan in what was hoped to be the final push.

Captured Japanese documents and post war interrogations of Japanese military leaders disclose that information concerning the number of Japanese planes available for the defense of the home islands was dangerously in error. During the sea battle at Okinawa alone, Japanese Kamikaze aircraft sank 32 Allied ships and damaged more than 400 others. But during the summer of 1945, American top brass concluded that the Japanese had spent their air force since American bombers and fighters daily flew unmolested over Japan.

What the military leaders did not know was that by the end of July the Japanese had been saving all aircraft, fuel, and pilots in reserve, and had been feverishly building new planes for the decisive battle for their homeland. As part of Ketsu-Go, the name for the plan to defend Japan -- the Japanese were building 20 suicide takeoff strips in southern Kyushu with underground hangars. They also had 35 camouflaged airfields and nine seaplane bases.

On the night before the expected invasion, 50 Japanese seaplane bombers,100 former carrier aircraft and 50 land based army planes were to be launched in a suicide attack on the fleet. The Japanese had 58 more airfields in Korea, western Honshu and Shikoku, which also were to be used for massive suicide attacks.

Allied intelligence had established that the Japanese had no more than 2,500 aircraft of which they guessed 300 would be deployed in suicide attacks. In August 1945, however, unknown to Allied intelligence, the Japanese still had 5,651 army and 7,074 navy aircraft, for a total of 12,725 planes of all types. Every village had some type of aircraft manufacturing activity. Hidden in mines, railway tunnels, under viaducts and in basements of department stores, work was being done to construct new planes.

Additionally, the Japanese were building newer and more effective models of the Okka, a rocket-propelled bomb much like the German V-1, but flown by a suicide pilot. When the invasion became imminent, Ketsu-Go called for a fourfold aerial plan of attack to destroy up to 800 Allied ships. While Allied ships were approaching Japan, but still in the open seas, an initial force of 2,000 army and navy fighters were to fight to the death to control the skies over Kyushu. A second force of 330 navy combat pilots were to attack the main body of the task force to keep it from using its fire support and air cover to protect the troop carrying transports.While these two forces were engaged, a third force of 825 suicide planes was to hit the American transports.

As the invasion convoys approached their anchorages, another 2,000 suicide planes were to be launched in waves of 200 to 300 , to be used in hour by hour attacks. By mid-morning of the first day of the invasion, most of the American land-based aircraft would be forced to return to their bases, leaving the defense against the suicide planes to the carrier pilots and the shipboard gunners.

Carrier pilots crippled by fatigue would have to land time and time again to rearm and refuel. Guns would malfunction from the heat of continuous firing and ammunition would become scarce. Gun crews would be exhausted by nightfall, but still the waves of kamikaze would continue. With the fleet hovering off the beaches, all remaining Japanese aircraft would be committed to nonstop suicide attacks, which the Japanese hoped could be sustained for 10 days. The Japanese planned to coordinate their air strikes with attacks from the 40 remaining submarines from the Imperial Navy -- some armed with Long Lance torpedoes with a range of 20 miles -- when the invasion fleet was 180 miles off Kyushu.

The Imperial Navy had 23 destroyers and two cruisers which were operational. These ships were to be used to counterattack the American invasion. A number of the destroyers were to be beached at the last minute to be used as anti-invasion gun platforms. Once offshore, the invasion fleet would be forced to defend not only against the attacks from the air, but would also be confronted with suicide attacks from sea. Japan had established a suicide naval attack unit of midget submarines, human torpedoes and exploding motorboats.

The goal of the Japanese was to shatter the invasion before the landing. The Japanese were convinced the Americans would back off or become so demoralized that they would then accept a less-than-unconditional surrender and a more honorable and face-saving end for the Japanese. But as horrible as the battle of Japan would be off the beaches, it would be on Japanese soil that the American forces would face the most rugged and fanatical defense encountered during the war.

 

[AJChenMPH]

Throughout the island-hopping Pacific campaign, Allied troops had always out numbered the Japanese by 2 to 1 and sometimes 3 to 1. In Japan it would be different. By virtue of a combination of cunning, guesswork, and brilliant military reasoning, a number of Japan's top military leaders were able to deduce, not only when, but where, the United States would land its first invasion forces.

Facing the 14 American divisions landing at Kyushu would be 14 Japanese divisions, 7 independent mixed brigades, 3 tank brigades and thousands of naval troops. On Kyushu the odds would be 3 to 2 in favor of the Japanese, with 790,000 enemy defenders against 550,000 Americans. This time the bulk of the Japanese defenders would not be the poorly trained and ill-equipped labor battalions that the Americans had faced in the earlier campaigns.

The Japanese defenders would be the hard core of the home army. These troops were well-fed and well equipped. They were familiar with the terrain, had stockpiles of arms and ammunition, and had developed an effective system of transportation and supply almost invisible from the air. Many of these Japanese troops were the elite of the army, and they were swollen with a fanatical fighting spirit. Japan's network of beach defenses consisted of offshore mines, thousands of suicide scuba divers attacking landing craft, and mines planted on the beaches. Coming ashore, the American Eastern amphibious assault forces at Miyazaki would face three Japanese divisions, and two others poised for counter attack. Awaiting the Southeastern attack force at Ariake Bay was an entire division and at least one mixed infantry brigade.

On the western shores of Kyushu, the Marines would face the most brutal opposition. Along the invasion beaches would be the three Japanese divisions, a tank brigade, a mixed infantry brigade and an artillery command. Components of two divisions would also be poised to launch counterattacks. If not needed to reinforce the primary landing beaches, the American Reserve Force would be landed at the base of Kagoshima Bay November 4, where they would be confronted by two mixed infantry brigades, parts of two infantry divisions and thousands of naval troops.

All along the invasion beaches, American troops would face coastal batteries, anti-landing obstacles and a network of heavily fortified pillboxes, bunkers, and underground fortresses. As Americans waded ashore, they would face intense artillery and mortar fire as they worked their way through concrete rubble and barbed-wire entanglements arranged to funnel them into the muzzles of these Japanese guns.

On the beaches and beyond would be hundreds of Japanese machine gun positions, beach mines, booby traps, trip-wire mines and sniper units. Suicide units concealed in "spider holes" would engage the troops as they passed nearby. In the heat of battle, Japanese infiltration units would be sent to reap havoc in the American lines by cutting phone and communication lines. Some of the Japanese troops would be in American uniform, English-speaking Japanese officers were assigned to break in on American radio traffic to call off artillery fire, to order retreats and to further confuse troops.

Other infiltration with demolition charges strapped on their chests or backs would attempt to blow up American tanks, artillery pieces and ammunition stores as they were unloaded ashore.

Beyond the beaches were large artillery pieces situated to bring down a curtain of fire on the beach. Some of these large guns were mounted on railroad tracks running in and out of caves protected by concrete and steel. The battle for Japan would be won by what Simon Bolivar Buckner, a lieutenant general in the Confederate army during the Civil War, had called "Prairie Dog Warfare." This type of fighting was almost unknown to the ground troops in Europe and the Mediterranean. It was peculiar only to the soldiers and Marines who fought the Japanese on islands all over the Pacific -- at Tarawa, Saipan, Iwo Jima and Okinawa.

Prairie Dog Warfare was a battle for yards, feet and sometimes inches. It was brutal, deadly and dangerous form of combat aimed at an underground, heavily fortified, non-retreating enemy. In the mountains behind the Japanese beaches were underground networks of caves, bunkers, command posts and hospitals connected by miles of tunnels with dozens of entrances and exits. Some of these complexes could hold up to 1,000 troops. In addition to the use of poison gas and bacteriological warfare (which the Japanese had experimented with), Japan mobilized its citizenry.

Had Olympic come about, the Japanese civilian population, inflamed by a national slogan - "One Hundred Million Will Die for the Emperor and Nation"
- were prepared to fight to the death. Twenty Eight Million Japanese had become a part of the National Volunteer Combat Force. They were armed with ancient rifles, lunge mines, satchel charges, Molotov cocktails and one-shot black powder mortars. Others were armed with swords, long bows, axes and bamboo spears. The civilian units were to be used in nighttime attacks, hit and run maneuvers, delaying actions and massive suicide charges at the weaker American positions. At the early stage of the invasion, 1,000 Japanese and American soldiers would be dying every hour.

The invasion of Japan never became a reality because on August 6, 1945, an atomic bomb was exploded over Hiroshima. Three days later, a second bomb was dropped on Nagasaki.

Within days the war with Japan was at a close. Had these bombs not been dropped and ha d the invasion been launched as scheduled, combat casualties in Japan would have been at a minimum of the tens of thousands. Every foot of Japanese soil would have been paid for by Japanese and American lives.

One can only guess at how many civilians would have committed suicide in their homes or in futile mass military attacks. In retrospect, the 1 million American men who were to be the casualties of the invasion, were instead lucky enough to survive the war. Intelligence studies and military estimates made 50 years ago, and not latter-day speculation, clearly indicate that the battle for Japan might well have resulted in the biggest blood-bath in the history of modern warfare.

Far worse would be what might have happened to Japan as a nation and as a culture. When the invasion came, it would have come after several months of fire bombing all of the remaining Japanese cities. The cost in human life that resulted from the two atomic blasts would be small in comparison to the total number of Japanese lives that would have been lost by this aerial devastation.

With American forces locked in combat in the south of Japan, little could have prevented the Soviet Union from marching into the northern half of the Japanese home islands. Japan today could be divided much like Korea and Germany. The world was spared the cost of Operation Downfall, however, because Japan formally surrendered to the United Nations September 2, 1945, and World War II was over. The aircraft carriers, cruisers and transport ships scheduled to carry the invasion troops to Japan, ferried home American troops in a gigantic operation called Magic Carpet.

In the fall of 1945, in the aftermath of the war, few people concerned themselves with the invasion plans. Following the surrender, the classified documents, maps, diagrams and appendices for Operation Downfall were packed away in boxes and eventually stored at the National Archives. These plans that called for the invasion of Japan paint a vivid description of what might have been one of the most horrible campaigns in the history of man. The fact that the story of the invasion of Japan is locked up in the National Archives, and is not told in our history books is something for which all Americans can be thankful.

 

[bulldogg]

Nice read LT... especially like you posting it up so I dont have to use a proxy to read the bloody thing.

 

[Gator]

Thing I don't understand is Japan is a small Island, they were pretty much beaten, they had no Naval Power left to speak of, their Land Based Aircraft were few and far between, Pilots lost.... why not just lock the entire Island down and either starve them out, or Bomb them into submission using Conventional Bombs?.... instead of getting many, many Americans killed trying to take the damn place by force on the ground.

It's all Monday Morning Quarterbacking though, as the Japanese were Nuked, not once, but twice.

 

[MontyB]

Thing I don't understand is Japan is a small Island, they were pretty much beaten, they had no Naval Power left to speak of, their Land Based Aircraft were few and far between, Pilots lost.... why not just lock the entire Island down and either starve them out, or Bomb them into submission using Conventional Bombs?.... instead of getting many, many Americans killed trying to take the damn place by force on the ground.

It's all Monday Morning Quarterbacking though, as the Japanese were Nuked, not once, but twice.

Because it had to come to an end and just leaving them there to starve really wasn't the answer. You have also remember there were thousands of allied POW etc that would have starved along with the Japanese and while there was no way the Japanese could have rebuilt a military there was every chance they would have created chemical/biological way to attack the allies.

In the end as with most wars boots on the ground was the only way it was going to end.

 

[perseus]

Admiral Ernest King also believed a naval blockade alone would starve the Japanese into submission. However, the American public would have seen such a policy as timid in view of the enormous resources and manpower available to them by that time, neither would Churchill have supported it.

The Soviets were waiting in the wings and would have few concerns about incurring casualties. Although I expect their amphibious capability was limited, their intervention in the North was on the cards.

The Allies also wanted to dispel the ‘myth’ of the superiority of the Japanese soldier since this would have seeded another excuse for a war at a later date.

Grand strategy in wars are really dictated by Politicians not military men.

 

[Gator]

Because it had to come to an end and just leaving them there to starve really wasn't the answer. You have also remember there were thousands of allied POW etc that would have starved along with the Japanese and while there was no way the Japanese could have rebuilt a military there was every chance they would have created chemical/biological way to attack the allies.

In the end as with most wars boots on the ground was the only way it was going to end.

Well they were on an Island, they would need to get the WMD off the Island somehow.
And there was no way of knowing how the Japanese would have reacted to being Nuked, not once, but twice, and what could have happened to the POWs because the Japanese got pissed off about the whole thing, seeing how Civilian Centers were the Targets.

There were a few POWs Nuked along with the Japanese, the United States of America was in the game to win, getting POWs back from Japan was just the icing on the cake.

My theory about what could have been was contingent on there not being a Nuclear Option (not to be confused with the 'Constitutional Option' of the Senate Democrats ending any proposed filibuster by the Senate Republicans when dealing with the Iraq War issue) so there is only the choice of either massive American casualties taking Japan by force, or locking Japan down and conventionally bomb them into submission, while not allowing them to get any supplies on the main Island.

 

[AVON]

Some of the Japanese troops would be in American uniform, English-speaking Japanese officers were assigned to break in on American radio traffic to call off artillery fire, to order retreats and to further confuse troops.

I hadn't heard that before. I have read in several Pacific island battles, the Japanese cryptographers had broken the US Army codes!

Had Olympic come about, the Japanese civilian population, inflamed by a national slogan - "One Hundred Million Will Die for the Emperor and Nation"
- were prepared to fight to the death.

One can only guess at how many civilians would have committed suicide in their homes or in futile mass military attacks.

The Japanese people were fully prepared to die. Even "IF" only half of them were willing to commit suicide that is still around fifty million people!! The Japanese Army informed the Emperor shortly before the atomic bombs were dropped that they expected 'at least' twenty million civilians to die in an invasion. If the Japanese Army used any biological or chemical weapons, the USAAF had thousands of tons of chemical bombs to be dropped by B-29 on the surviving populated areas all over the country! The US was prepared for that contingency.
Even if the US was willing to wait, it is for sure Stalin was not afraid to loose people and he would have invaded in the last of 1945 or early 1946.
NOTE:
The invasion of the home islands of Japan planning started in February of 1942, at the request of President Roosevelt! Each island after it was captured was used as a storage facility to enhance the invasion efforts.

With American forces locked in combat in the south of Japan, little could have prevented the Soviet Union from marching into the northern half of the Japanese home islands. Japan today could be divided much like Korea and Germany.

I would have liked to see the Soviet invasion plans. It would not have been a cake walk for them. The Soviets did not have a massive amphibious fleet, and the terrain greatly favored the defenders being very mountainous, in the northen half of the Island of Honshu.

Thing I don't understand is Japan is a small Island, they were pretty much beaten

Actually, Japan (145,916 sq mi) is about 10% smaller than the state of California (163,670 sq mi) and, fifty percent larger than the UK (94,526 sq mi)! The island is larger than most people think it is.

they had no Naval Power left to speak of, their Land Based Aircraft were few and far between, Pilots lost....

No it did not have much of a navy left but, it had dozens of suicide submarines, hundreds of speed boats (packed with explosives) hidden in caves were to attack the amphibs and, over 8,000 kamkazis aircraft! It was not until after the war did the US military find out about the "hundreds" of caves that the Japanese had weapons in. Aerial reconnaisance was not able to see these caves. Caves less than twenty miles from the amphibious ships traveling in the fog or at night, these speed boat would have cause many casualties among the amphibious forces. Kamikazi aircraft taking off from rough airfields where caves had been used as aircraft hangars. After taking off, flying low to take advantage of the fog to protect them from the "Blue Blanket" of Hellcats.
Unlike Okinawa, there would be little radar warning time of an air attack. The Japanese plan was to kill three divisions of US troops (30,000 troops) before they got to the beaches! November is a foggy month around Japan. Many factors favored the Japanese efforts that they did not exist in previous efforts to oppose a US amphibious invasions. (The US Navy lost about 15% of its 'entire wartime casualties' at the Battle of Okinawa Island, or rather in the Navy's case, the control of the waters around the island.)
The invasion of Japan was planned by the Japanese to be like the first six hours on Omaha Beach except, the Japanese planned that intensity would last at least a week or more! The Japanese wanted the casualties to be so high the US government would accept peace on Japan's terms! (Yeah.... I want lower taxes and world peace also.)

why not just lock the entire Island down and either starve them out, or Bomb them into submission using Conventional Bombs?.... instead of getting many, many Americans killed trying to take the damn place by force on the ground.

The Japanese were prepared to die that way, should it come. Sooner or later ground troops would have to occupy the island. I don't think the American people would have been willing to wait until 1947 to see if, the Japanese would have been willing to give up because they were starving. The majority of the Japanese national leaders were of the mindset, that it would be better that all Japanese people die rather than to live in disgrace in a land occupied by foreign soldiers!

Because it had to come to an end and just leaving them there to starve really wasn't the answer. You have also remember there were thousands of allied POW etc that would have starved along with the Japanese and while there was no way the Japanese could have rebuilt a military there was every chance they would have created chemical/biological way to attack the allies.

In the end as with most wars boots on the ground was the only way it was going to end.

Exactly!

You have also remember there were thousands of allied POW etc that would have starved along with the Japanese

No, at the first efforts to invade, the Japanese Army planned to execute all two hundred thousand Allied POWs!

there is only the choice of either massive American casualties taking Japan by force, or locking Japan down and conventionally bomb them into submission, while not allowing them to get any supplies on the main Island.

Can you imagine the riots in US cities if we invaded the island and had over 10,000 casualties and the people found out the US scientist had developed a weapon (at a cost of $5 billion -1945 dollars), that could have spared the lives of the US troops. The president and the Congress would have been removed!!!
Remember Adm. Halsey received hate mail for six months because of the casualties suffered in the invasion of Tarawa Island!

 

[Britney]

interesting read, downfall would have been horrible within 90 days of cornet and hornet it was estimated the US alone would have suffered 1.5 million casualties and 300,000 allied POWs would have been executed.