Atomic Bomb Section 2 Japan’s defenses, what we knew then compared to what was reality
The Japanese understood that the war was lost. They had no thought of being able to pull victory from defeat; their only thought being how to make the defeat as painless as possible. With this in mind, they began to plan the defense of their home islands. They understood that Americans would only accept so many casualties and the more they inflicted, the easier it would be to demand conditions for their surrender. The military leaders of
The first time the military planners had any idea things were out of the ordinary was a report on
Looking at records captured after the end of the war and declassified intercepts from that time revealed that
After taking the beaches, the
They were also masters at using natural caves, fortifying them and expanding them. Central living and command rooms were sometimes sixty feet inside the hills. Lateral tunnels led out to hillside openings and gun positions. Gun crews could pull their weapons inside in case they were discovered or came under heavy fire. On some islands, caves were found with up to nine levels of living quarters and could house 200 men. On
These caves were nearly impervious to naval bombardment, artillery or aerial bombing. They were built to support each other as well with interlocking fields of fire. They were protected on all sides and even after a hill was taken, they had nearly as hard of a time fighting their way down the back side because of the extensive preparations.
Despite all of our best efforts, there was very little in the way of innovation when it came to taking these prepared positions. A special project was even formed to try and discover new ways to defeat them, project “SPHINX.” Despite all best efforts, little was accomplished. Most of what was done was improving on what already worked, that being hand held and tank mounted flame throwers. Newer, longer range flamer throwers were developed to help the troops have some stand-off range. Flame thrower crews had some of the highest casualty rates of infantry men during the war.
Some felt these preparations by the Japanese were in vain since self-propelled 8-inch weapons and 155mm howitzers as well as tanks could destroy these bunkers. This is true of the original defenses set up by the Japanese early on, but they learned as well. This was discovered on
Similarly, many have felt that
There were thousands of Japanese ready to commit suicide to save the home islands; far more than had been anticipated. The Kamikaze would be in the air on land and at sea. If a Kamikaze could kill only one American, it was worth the sacrifice; if they could destroy and entire ship, it would be bliss.
When the initial casualty estimates were created by Marshall and others, it was thought that there would be no more than 2,500 aircraft to oppose the landing. In reality, nearly 12,000 aircraft awaited the invasion fleets arrival. The Imperial Army planned to send these planes out in waves of up to 400 at a time. They would send more suicide planes in 3 hours than they did in three months at
The Imperial Army had high hopes for their Kamikaze pilots. They projected that under favorable conditions, their pilots could destroy 50% of the invasion fleet before it ever reached the shores. On the low end, in bad conditions, they still felt that they could destroy 30% of the fleet.
Their Kamikaze hopes were not limited to the air; they also had manned suicide boats to throw at the invaders. While not strictly suicide boats, 2 types of submarines were available to attack invading ships. The survival rates for those serving on these submarines were so low that it might as well have been suicide. The first, the Koryu class carried 2 torpedoes. They had approximately 110 of these submarines ready for action. There was a smaller version of this called the Kairyu class which either had two torpedoes or, alternately, 600 kilograms of explosives packed in the nose for a suicide ramming mission. There were about 250 of these submarines available. Finally, about 1000 Kaiten were available. The Kaiten was basically a manned torpedo. Next were the Shinyo boats. These were single crew, small boats that carried two 120 kilogram depth charges. Their goal was to ram transport ships and blow them up. There were approximately 6,200 of these boats ready for use. Shinyo boats had been used in the
The final part of this intricate plan was the civilian population. At first, the thought was to evacuate the civilians until they quickly realized they had no place to move them to, no vehicles to move them with and nothing to feed them if they were moved. Therefore, in March, the Imperial Army decided to make the civilian population part of the reinforcements. Nearly 10,000,000 civilians lived on
At the end of March, the Patriotic Citizens Fighting Corps was formed. All men ages 15-60 and women 17-40 were subject to being called to duty. The term “cannon-fodder” comes to mind when thinking of these civilians. They had no uniforms, no weapons and little training. They were taught to use farming implements and other items to fight with. They were taught that if they were only able to kill one American, they had done their part to protect the homeland.
This is what awaited the American invaders: 900,000 soldiers, 12,000 kamikaze pilots, thousands of kamikaze boats, submarines, manned torpedoes and suicide swimmers. There were fortifications dug in over the entire island and the Imperial Army was determined to meet those soldiers that came ashore on the beaches. Millions of civilians stood ready to help the soldiers in anyway they could. It was setting up to be one of the bloodiest battles in history. If, for some reason, the battle had been delayed even further, the number of Japanese soldiers trained and waiting could have reached into the millions. Luckily, it never happened. It is easy to see how the estimates of
While the Americans never realized the full extent of what was waiting for them, because of their ability to intercept and decode Japanese messages, a clearing picture was starting to form. For example, they soon realized that the number of soldiers they would be facing was much more than 350,000. Although they didn’t know the actual amount, their revised estimate was closer to 600,000 enemy soldiers. They realized their initial estimates were far from accurate and the more messages they intercepted, the more concerned they became. It got to the point where leaders started to seriously question the wisdom of continuing with Operation Olympic. Admiral Nimitz had early on felt the operation was ill conceived, others were now in agreement. Still, a better plan was not forthcoming and time was running short. Until the atom bombs were dropped, Operation Olympic was a go.