"Sun Tzu's Art of War" Yun: Those who do not know the harm of using soldiers cannot fully know the benefits of using soldiers. The initiators of a war do not start a war blatantly because of a momentary fever. An important and necessary condition for waging a war is that the benefits of waging a war outweigh the disadvantages of waging a war.

In the "History of Japan", it is mentioned that on October 24, 1929, the US stock market plummeted, and the so-called Black Tuesday caused chaos and crisis in the world economy. At that time, there were no institutions or mechanisms in the world that could cope with such an international economic crisis. The following year, Europe was also embroiled in the great crisis. Further contraction of Japan's domestic market in the midst of tightness is inevitable, and the worldwide crisis has affected its exports, which is really worse. The average price of eight important commodities in Japan has fallen by 37%, small and medium-sized enterprises have gone bankrupt in large numbers, and it has become common for workers to be laid off, wages to be cut or labor intensity to increase.
If the aggressor goes unpunished and plundering always succeeds, how can the aggressor stop committing murder and robbery? Ambitions for external expansion are constantly expanding, and militarism is thriving in Japan.
War, a war of aggression against the outside world, has become the only feasible way to solve this problem. The economic crisis and natural disasters have caused serious damage to Japan's national economy, making the Japanese ruling clique eager to completely seize the vast land, abundant resources and investment of 1.4 billion yen in northeast China. At this time, the Northern Expedition war broke out in China, and the people's revolutionary movement was also developing vigorously. Also during the same period, the political situation in Japan also underwent turbulent changes. On April 2 of the same year, the Political Friends Association was established, headed by army general and warlord Yoshiichi Tanaka. Tanaka was a fanatical militarist leader who was always keen on invading China. After he came to power, he announced the policy of the Tanaka cabinet. On China policy: "As for the activities of the Communist Party of China, depending on their outcome, the position of our country, which is directly affected by it, and Japan, which bears a heavy responsibility for maintaining the overall situation in East Asia, cannot be regarded as irrelevant. The intention is to further promote Japan's internal affairs and expand the "active policy" of invading China.
Prompted by Japan's own economic recession, japan's militarist ideas of aggression and expansion have reached new heights.
In "Inside the Japanese Military Situation," it is mentioned that the various japanese organs of aggression entrenched in northeast China, domestic military and political dignitaries, and representatives of right-wing organizations have published articles, published pamphlets, given speeches everywhere, distributed leaflets, and fanatically clamored for the theory of "Manchuria and Mongolia being special," "Manchuria and Mongolia are Japan's lifeline," and That Japan's occupation of northeast China "is a matter of course," and so on, thus creating all kinds of "theoretical bases" for Japanese imperialism to launch a new war of aggression against China. All these circumstances show that the Japanese imperialists' plot to invade northeast China has been laid out with a bow and arrow, and is ready to attack.
War was on the verge of breaking out, and Japanese imperialism frequently provoked incidents in order to create a pretext for launching a war of aggression.
In the spring of 1931, the Japanese Kwantung Army formulated a specific plan to explode the South Manchuria Railway near Wicker Lake, and at the same time take the opportunity to attack the North Camp of the Northeast Chinese Army and capture Shenyang. At 22:20 on September 18, Lieutenant Kawamoto, a Japanese sapper, led six soldiers to place 42 packages of small yellow explosives on the South Manchuria Railway, 800 meters from the North Camp, in the name of patrolling the railway, and then lit the explosives and blew up a section of the railway. With the sound of an explosion, the Japanese began to attack the North Camp. Under Zhang Xueliang's "policy of non-resistance" of Chiang Kai-shek, the Japanese army easily occupied the North Camp and captured Shenyang according to the predetermined plan. Soon the Nationalist government lost the important town of Shenyang. By September 25, the Japanese Kwantung Army had completed the first phase of the plan for the incident, and Japan's conspiracy to create the "918" incident had basically succeeded. The goal of the second phase was to capture Heilongjiang Province. On October 19 of the same year, the Japanese puppet army occupied Qiqihar, and then turned to Jinzhou to seize the entire western Liaoning region. In just 4 months and 18 days, the Japanese army occupied the entire three northeastern provinces of China.
As a result of the repeated success of aggression and the acquiescence and encouragement of the Western powers, the war fanaticism of the Japanese fascists was even more unbridled. In order to let go of the aggression of China, it simply announced its withdrawal from the "League of Nations."
Northeast China is a heavy industrial base. Under the cover of Japan's invasion war, it became a base for Japan to plunder various industrial resources, and these industrial resources were continuously flowed to Japan, which was scarce in resources, and Japan's economy slowly began to recover and gradually got rid of the economic crisis. But none of this satisfies Japan's ambitions. By 1936, Japan's military expenditure had more than doubled from 1931, accounting for 47% of the gross national product, and the military industry began to rise abnormally, which made advance preparations for a deeper invasion of China.
Under the unusually smooth start of the war of aggression and the considerable benefits brought about by this war, the arrogance of Japanese militarism has become even more arrogant, and it has even more clamored for "the destruction of China in three months."
After tasting the sweetness brought about by the "918" incident, he attempted to launch a full-scale war of aggression against China through the "July 7" incident to completely conquer China. However, with the expansion of the theater of operations and the extension of the front, the Japanese army dispersed its strength and the illusion of destroying China was shattered.
After the early strategic defense, it began to shift to the medium-term strategic confrontation, and the Japanese army began to lose sharply. Due to the limitations of Japan's territory, the quality of the source of soldiers began to gradually decrease. The Japanese army began to tire of fighting, and with it, the Japanese army became more brutal to the Chinese people. Seeing that most of China's territory has fallen into the hands of the enemy. Zhang Yang (Zhang Xueliang, Yang Hucheng) launched the "Xi'an Incident" that shocked China and foreign countries. Under the mediation of the Chinese Communist Party, the "Xi'an Incident" was resolved peacefully. The Kuomintang and the Communists cooperated again to begin a unified war of resistance, the all-out War of Resistance kicked off, and the war began to change from strategic confrontation to strategic resistance.
After several years of war, the japanese army's living forces have been almost exhausted, and by the end of the period, the source of Japanese troops is basically teenagers. The outcome of the war is already clear. On the Chinese battlefield, the Japanese suffered 1.5 million casualties. The war ended with unconditional surrender.
Throughout the war, the harm to Japan outweighed the benefits. After the end of the war, How Japan ate its territory, it spit it out. Japan's biggest mistake was to choose the wrong opponent, and China is a country that looks ordinary, but it is also a country that no country can afford. In China's five-thousand-year history of war, there has never been a single page of history in which it was completely invaded by foreign countries and has always been subservient to the enemy.