Therefore, in order to force Japan to surrender, a landing war against Japan seems inevitable, and both the United States and Japan are well aware of this. To this end, Japan put forward the slogan of "100 million pieces of jade", while the United States formulated a "decline action" in a targeted manner.
As early as 1943 Quebec meeting, the joint planning group of the United States and Britain had actually put forward a plan of "evaluating and planning to defeat Japan", which pointed out that the attack on Japan should not be earlier than 1947 or 1948, but this plan was immediately opposed by the Joint Chiefs of Staff, because they thought that excessively prolonging the war would damage the morale of the country.
According to the original plan of the allied forces, in order to avoid more casualties, they hoped to force Japan to surrender through sea blockade and air strikes under the increasingly obvious situation in the Pacific battlefield, so they had the "island-jumping tactic". As the US military got closer and closer to Japan, the scale and frequency of bombing against Japan began to increase.
At the same time, the Japanese side is actually very aware of the result of defeat, but they are more willing to sign an armistice agreement or accept conditional surrender than unconditional surrender of complete defeat. To this end, Japan hopes to force the allies to sit at the negotiating table by causing painful casualties to the allies. In the case of losing air and sea control, landing defense is their only chance to achieve this goal. To this end, Japan put forward the slogan of "100 million pieces".
1944, after the US military occupied the Mariana Islands, it began a continuous large-scale bombing of Japan. For this reason, the US Army placed the 20th Air Force under the 2 1 Bomber Command, and the 73rd Bomber Wing also entered Saipan in Mariana Islands.
From June/KOOC-0/944, June/KOOC-0/65438+/KOOC-0/0 to August/KOOC-0/945, the US Air Force strategically bombed 98 cities in Japan, dispatched 33,000 B29 bombers and dropped/KOOC-0/60,000 tons of bombs. In order to cause more casualties, the US military even changed the bombs into incendiary bombs, which directly led to 24% houses in Japan. Tokyo, Japan is the most seriously damaged city, with three explosions in 1945 and 140000 people killed.
However, under the continuous bombing of the US military, Japan never showed any signs of surrender, so the US Air Force proposed to seize the air bases in Shanghai and North Korea, thus launching a larger bombing of Japan. However, more generals, including Marshall, have deeply realized that landing operations may be inevitable in order to force Japan to surrender.
In order to ensure the success of the landing operation, the US military began to formulate the landing operation plan while continuing to bomb Japan.
The first task of the landing plan is to choose the landing site, but because there are few beaches suitable for landing in the Japanese archipelago, it is almost the only possibility to directly threaten Japan's political center by capturing the Kanto Plain in order to force Japan to surrender faster. Therefore, the US military finally decided to land on the beaches in southern Kyushu and southern Kanto Plain in Honshu Island.
Therefore, the plan of "Decline Action" including "Olympic Action" and "Little Crown Plan" was formulated.
1, Olympic action. The purpose of this action is to provide a forward support base for the landing operation in the southeastern plain of Guandong by capturing the southern part of Kyushu Island, the southernmost tip of the Japanese archipelago (about one third of the whole island), thus ensuring the ultimate success of the landing operation.
It is planned to be launched on June 5438+0945, 1 65438+1October1. The landing force is the sixth army of the United States, which has jurisdiction over the first, ninth and eleventh armies. At the same time, it dispatched a huge fleet including 24 aircraft carriers, 24 battleships, more than 400 destroyers and frigates, and the 20 th Army provided air support. In addition, the Commonwealth Joint Fleet including 12 aircraft carrier and several battleships, the bomber unit nicknamed "Tiger Force" and Australia's First Tactical Air Force will also participate in this operation.
The plan also includes a deception plan codenamed "Operation Colored Crayon" (that is, the US military abandoned the landing, but still forced Japan to surrender by encircling and bombing), as well as landing operations against the islands around the Japanese archipelago, such as Tanegashima, Yakushima and Saidao.
2. Little Crown Project. The purpose of the plan is to launch a landing operation on the beach south of the Kanto Plain in Japan, then occupy the Kanto Plain and Tokyo in the north, and finally force Japan to defeat and surrender.
The plan is scheduled to be launched in March 1946 1. At that time, the First Army and the Eighth Army of the US Army will land in 99- Li Bin on the General Peninsula and Hiratsuka City in Sagami Bay respectively. After landing, the two armies will go north and eventually meet in Tokyo. In addition to the 25 divisions that launched the landing operation, the US military will also deploy the second echelon of 13 to 15 divisions.
By the summer of 1945, when the plan was redefined, almost all the allies promised to provide ground troops for the implementation of the plan, with a total of about 1 10,000 people.
According to the plan, the US military will invest as many as 2.5 million troops in the "Decline Operation". Because of this, the army and air force on the European battlefield will not be able to return home, and even take out troops including 15 Army Division and 63 Air Force Brigade and redeploy them in the Pacific region.
As mentioned earlier, in order to push the allied forces to the negotiating table, Japan is also actively formulating a local defense plan, that is, an "absolute" plan. Compared with the allied forces, Japan naturally knows more about the key points of local defense, so they put their main forces in Miyazaki, Youming Bay and Samo Peninsula, which are most likely to be attacked in South Kyushu.
By the end of the war, due to the heavy losses of pilots and the backwardness of aircraft and ships, Japan began to rely more and more on suicide "Kamikaze special attack". To this end, the Japanese army handed over almost all aircraft, including trainers, to the special team in an attempt to make up for the lack of quality by quantity. At the same time, Japan also produced hundreds of suicide attack boats to deal with allied ships near the coast of Kyushu.
After learning the experience of island defense in the later period, Japan decided not to stick to the beachhead position at the risk of naval guns and bombing, but to retreat its defensive troops to a few kilometers away from the coast. This can avoid the attack of allied naval guns, and it is difficult for landing troops to establish an effective foothold because of the narrow space. In addition, the Japanese army also arranged a counterattack force behind the defense line in order to quickly support places with greater pressure.
At the same time, after learning from the defense experience of Iwo Jima and Okinawa, the Japanese army knew that in the absence of air and sea control, it was almost "throwing eggs at stones" to fight head-on with the US military, so it chose to build a large number of underground fortifications to ensure the greatest casualties to the landing troops. In Nagano Prefecture, the Japanese army even built underground fortifications as the highest headquarters of the Japanese army after the fall of Tokyo.
In order to ensure the defense force, the Japanese army began to send more troops to Kyushu Island in the spring and summer of 1945, and mobilized a large number of troops from Manchukuo, North Korea and North Japan, which increased Kyushu's strength from one division in March to 14 division and three tank brigades, with more than 900,000 troops, and allocated 40% of the total ammunition in the country to Kyushu's defense force.
At the same time, in order to make up for the decline in the quality of soldiers in the late war, Japan decided to exchange quantity for quality. To this end, they launched a national mobilization and organized a national volunteer fighting team of up to 28 million people, including1any healthy male aged 5 to 60 and1female aged 7 to 40.
Although Japan has been unable to provide weapons and equipment to so many people at this time, their childlessness is extremely terrible. Richard B. Frank, an American military historian, recorded in "Decline Action-The End of Japanese Empire" that a recruited high school girl was given an awl and told that "it is ok to kill an American soldier".
It can be said that Japan has devoted almost all its strength in this unprecedented defensive war, and their goals are also very clear. Even if we can't win the final victory, we will try our best to cause huge casualties to the allies, thus forcing them to give up their plan to occupy Japan in an all-round way and exchange them for bargaining chips.
While formulating the "Operation Descent" plan, the US military has begun to assess the resistance and casualties that may be encountered during the landing operation. The results of the evaluation made everyone gasp, and with the change of the situation in the late war, the United States finally chose to give up the plan.
1, huge casualties. The first is the air threat. The U.S. Navy estimated the aircraft owned by the Japanese Kamikaze Special Forces, and the predicted result is that Japan will have more than 10000 aircraft 1945 by August. In the battle of Okinawa, the Japanese army successively invested nearly 2,000 suicide planes, with a hit rate of about 9: 1. In the defensive operations in Kyushu, with the help of local advantages and quantitative advantages, the US military predicted that the hit rate would probably increase to 6: 1, and more than 400 allied ships, mainly suspicious transport ships, would be sunk. Some even predicted that one-third to one-half of the landing troops would be raided by kamikaze commandos.
The second is the land threat. Since April 1945, the intelligence department of the allied forces has noticed the increase of Japanese troops, and the US military authorities believe that "the force to resist the attack will not only come from organized military forces, but also include fanatical hostile elements". To this end, based on the experience of previous battles, the United States Joint Staff issued a research report in April 1945, stating that "the death rate per thousand people in the US military is 1.78, and the casualty rate is 7.45."
According to estimates, if the Olympic plan lasts for 90 days, the US military will pay about 450,000 casualties, including about 654.38+10,000 deaths. If Operation Little Crown lasts for 90 days, the total number of casualties will be as high as 1.2 million, including about 260,000 deaths. Among them, only General Nimitz considered the casualties at sea, and he thought that the ratio of the losses caused by Kamikaze special forces to those caused by Japanese pilots would reach 1.78: 1.
According to a report written by united states secretary of war Stimson's aides entrusted by william shockley, he thought that if the Japanese were to be conquered, the US military would have to pay 654.38+0.7 million to 4 million casualties, including 400,000 to 800,000 deaths, which even exceeded the casualties paid by the US military in the whole World War II. Obviously, American policymakers and domestic public opinion can't afford such huge casualties.
2. Changes in the strategic situation. After Germany's defeat and surrender, the European War basically ended, and the Soviet Union officially declared war on Japan on August 8, 1945. Soon,1500,000 Soviet Red Army entered the northeast of China and launched an attack on the Japanese Kwantung Army.
After the end of World War II, when the direction of the war has gradually become clear, the new pattern of the post-war world has gradually become clear. Corresponding to the weakness of the old empires such as Britain and France, the hegemony of the United States and the Soviet Union was basically consolidated. Therefore, how to occupy a dominant position in the post-war world structure and gain strategic advantages has been put on the table. If the expansion of the Soviet Union in Eastern Europe cannot pose a threat to the United States because of the containment of Britain and France, then the expansion of the Soviet Union in the Far East cannot but attract the attention of the United States.
At the end of the war, whether facing the United States or the Soviet Union, the Japanese army was powerless to resist. Then, if the US military cannot force Japan to surrender as soon as possible, with the continuous eastward shift of the strategic center of gravity of the Soviet Union, the interests plundered by the Soviet Union will naturally increase day by day, and correspondingly, the strategic influence of the Soviet Union in the Far East will inevitably increase.
In fact, after occupying Sakhalin Island and Kuril Islands, the Soviet Union is secretly preparing to continue to attack Hokkaido. If this is the case, then it is very likely that the Soviet Union will launch a landing operation with the US military, and as a result, it will eventually carve up Japan with the United States like the Allied occupation of Germany, which is obviously unbearable for the United States.
Therefore, Marshall was anxious to launch an attack before1August 945 15 at the latest. However, because the whole plan has not been finalized within the United States, and in order to ensure the smooth implementation of the landing plan, the United States still needs to transfer 15 army divisions and 63 air force brigades from the European battlefield, so that the troops invested by the United States will reach 2.5 million, which is impossible in a short time. Therefore, the United States government,
Therefore, when the world's first atomic bomb was successfully tested in Bikini Atoll in the Pacific Ocean on July 25th, 1945, in order to avoid heavy casualties and the expansion of the Soviet Union in the Far East, Japan was forced to surrender unconditionally at the fastest speed, and the American decision-makers finally chose to drop the atomic bomb in Japan and gave up the landing plan "Decline Action".