the Nomenkan incident finally made the Japanese government and public tend to the Navy’s Southward Policy. The status of China’s battlefield has also changed 180 degrees from cooperating with the north. In 1940, Japanese forces invaded French Indochina. As the contradiction with Meiwei could not be reconciled, general Yamamoto’s sneak attack plan finally turned the southward advance from imagination into reality.

I. background of the Nomenkan incident

after the Japanese imperialists occupied Northeast China, they began to take the Soviet Union as an imaginary enemy, gradually enrich and strengthen the Kanto army stationed in Northeast China, and their policy towards the Soviet Union was further tough. In order to ensure the security of its territory in the Far East, the Soviet Union continued to enhance its military strength in the Far East. By June 1934, the Far East Soviet army had 11 infantry divisions, two cavalry divisions, 650 tanks and 500 aircraft, with a total force of about 230000. At that time, Japan’s military strength in Northeast China was only three divisions, one mechanized brigade, one cavalry group and three independent guard teams, with about 80 aircraft and a total military strength of about 50000 people. Even with the military strength in North Korea, it was less than half of that of the Soviet army in the Far East. From this, Japan felt the great threat of the Soviet Union, and the rapid expansion of armaments is imperative.

1935, Hiroshi Ishihara, chief of the operations section of the General Staff Headquarters of Japan, believes that: “In terms of China’s national strength, it is impossible to strengthen our army and Navy armaments against the Soviet Union, the world’s strongest army country, and the United States, the world’s largest Navy country at the same time. It is impossible to support a long-term war only if the armaments are strengthened without the material power of war – resources and production capacity. If the current situation continues to develop, it may be trapped in bringing the Soviet Union, the United States and Britain into conflict At the same time, China and China are treated as enemy countries. Therefore, we must focus on war preparedness against the Soviet Union, eliminate threats from the north, prevent the breakdown of relations with China, and try our best to maintain cooperation with the United States and Britain. In this period, we need to cultivate Manchukuo. ” It can be seen that Japan’s idea is to put the North advance in the first place. To achieve this goal, we must also agree with the Navy on national defense policies. However, since the end of 1936, the Japanese Navy has not been restricted by the Treaty on the limitation of naval armaments, so it is also eager to strengthen the armament of the Navy. In addition, the Japanese Navy held a “strong distrust attitude” towards the “uncontrolled practices” of the army’s activities in North China and Inner Mongolia after the September 18th Incident. In this way, the Navy strongly advocates “guarding the north and marching south”.

in January 1936, the Japanese military command proposed to revise the imperial national defense policy for the third time. In the process of revision, there was a fierce dispute between the army and the Navy, and finally formed a compromise scheme to reconcile the opinions of the army and the requirements of the Navy. The final amendment stipulates: “in view of the original meaning of imperial national defense, imperial national defense may have the greatest necessity of conflict with China, and it is aimed at strong national strength, especially the United States and Russia with strong armaments. At the same time, it should guard against China and Britain.” On April 16, 1936, the Navy formulated the outline of imperial national policy, which stipulates that “the fundamental policy is to change the common government internally, ensure the status of the imperial mainland externally, and develop to the south at the same time.” On the basis of the above-mentioned idea of Hiroshi Ishihara, the army formulated the outline of national defense policy. Its basic idea is “first of all, make every effort to subdue the Soviet Union, and then use its strength to expel British forces in East Asia, seek goodwill between Japan and China, and prepare for a decisive battle with the United States.” In this way, the operational purposes of the land and navy are self and common. As a result, the army and Navy realized a compromise, and the arrogant Baida’s policy of “going north and South” was established. On August 7, 1936, at the “five phase meeting” attended by the prime minister, the foreign minister, the Continental, the marine and the Tibetan ministers, it was decided to take the outline of national policy as the “benchmark of national policy”, which determined the aggressive strategy of “ensuring the status of the Empire in the East Asian continent on the one hand and developing towards the Southern Ocean on the other hand”.

on the same day, the four phase conference formulated the imperial diplomatic policy adopted to realize this national policy: “focus on smashing the Soviet Union’s attempt to invade East Asia, especially eliminating the threat of armaments and preventing the expansion of red industrialization”; For China, the focus is “first of all, make North China quickly become a special colonial area against communism and pro Japanese Manchu”; For the United States, “at present, we should respect the interests of the United States in conducting business with China” and “strive to enhance friendly relations and try our best not to obstruct the empire from realizing its East Asian policy”; For Europe, “adjust Japan UK relations” and “implement Japan Germany cooperation”; For Nanyang, “committed to peaceful and progressive expansion and development.”

according to the above policy, Japan has adopted a series of heavy fire activities in diplomacy. First of all, with the Soviet Union as its imaginary enemy, Japan continues to send more troops to Northeast China.

secondly, as an important part of Japan’s invasion plan, Japan launched a comprehensive war of aggression against China. By October 1938, the Japanese invaders occupied Guangzhou and Wuhan. However, the Japanese strategic attack in China also reached the peak, and the Anti Japanese War entered a stalemate stage.

third, because we should “respect the interests of the United States in China and strive to enhance friendly relations”, we cannot take direct confrontation with the United States. Therefore, in view of the powerful US Navy, Japan adopted a “silent” way of military expansion – under the condition of absolute confidentiality, it began to build “Yamato class” super battleships, accelerated the construction of “Xianghe” and “Ruihe” heavy attack aircraft carriers, and modernized and heavy refitted a large number of heavy cruisers and light cruisers.

fourth, Japan stepped up its cooperation with fascist Germany in Europe. On July 24, 1936, the Japanese cabinet made a resolution to ensure the smooth implementation of Japan’s security and mainland policy. We must unite with other countries to contain the power of the Soviet Union in order to reduce the threat to Japan. Therefore, in November 1936, Japan and Germany signed the notorious “anti communist international agreement”.




the signing of the anti communist international agreement marked the further strengthening of Japan’s policy towards the Soviet Union. Because with the expansion of Japan’s invasion of China, there was a conflict with Western forces in China. In this way, Japan needs to further play the banner of anti Soviet in exchange for the connivance of western countries to Japan’s invasion of China. For the Soviet Union, the anti Communist International AssociationAfter the signing of the treaty, the Soviet Union was under the attack of two fascist countries. In order to reverse the unfavorable situation, the Soviet Union signed the “non aggression treaty” with the Chinese government on September 28, 1937 to vigorously assist China in the war of resistance against Japan. According to Soviet data, from October 1937 to September 1939, the Soviet Union supplied 985 aircraft, 82 tanks, more than 1300 guns, more than 14000 machine guns and other weapons and equipment to the Chinese central government. The Soviet Union also sent volunteer pilots to directly participate in China’s war of resistance against Japan.

the Japanese Navy began a series of actions to advance southward according to the imperial national defense policy, imperial foreign policy and Zhou policy benchmark formulated in 1936. In September 1936, Kobayashi Jizao, a senior general of the Navy, was appointed governor, and the post of governor of Taiwan, which had long been occupied by civil servants, was changed to military attach é of the Navy. In April 1934, the new navy was set up and was mainly responsible for the policy of Nanjin. In February 1939, the Japanese Navy occupied Hainan Island and then a series of islands in the South China Sea. With the implementation of Japan’s Southward Policy, the contradiction with Western powers became increasingly acute. In late June, Dutch East India cut the import quota of Japanese cotton products, cotton cloth and ceramics by half. On July 26 of the same year, the United States announced the abolition of the Japan US trade treaty. During the week, Japan was extremely poor in resources and highly dependent on foreign countries for war preparedness materials. Therefore, the tough policy of the United States has dealt a heavy blow to Japan.

in the north, the Japanese Kwantung Army mainly carried out armed provocation in the Sino Soviet border area, and successively provoked the zhanggufeng incident and the Nomenkan incident. There are two main motives for Japan’s armed provocation against the Soviet Union: first, it attempts to continue to use its tough policy towards the Soviet Union to test the strength of the Soviet army through local war, so as to deter the Soviet Union and force the Soviet Union to abandon its position and principle on the issue of Japanese aggression against China; The second is to use the armed provocation against the Soviet Union to create a human scale anti Communist smoke screen and divert the attention of western countries, so as to exchange the appeasement of the two countries to Japan’s invasion of China and reduce the pressure from the United States and Britain caused by the Southward Policy.




the so-called Zhang Shufeng incident refers to a border military conflict between Japan and the Soviet Union to compete for Zhang Gufeng and shacao peak from late July to early August 1938. The Soviet Union also called this incident Hassan Lake incident. In 1938, Japan proposed to the Soviet Union to designate Zhang Gufeng and the shore of Hassan lake near him to the puppet Manchukuo. After being rejected, Japan sought an excuse to ask the Soviet Union to withdraw its troops from Zhang Gufeng, which was rejected again. Japan and the Soviet Union began to assemble troops in the border areas. On July 29, the Japanese army suddenly invaded the territory of the Soviet Union and occupied several highlands. In order to support the army, the Japanese command also transferred a ship squadron to the Tumen estuary. On August 6, the Soviet Union sent the 39th infantry army to the combat area and turned to the counter offensive with the cooperation of tanks and aircraft. The battle lasted until August 9, when the Japanese army was defeated miserably. Finally, they had to put forward a truce proposal to the Soviet Union. After consultation, the two sides signed a truce agreement on August 10, and formally cease fire with the Soviet Union in August.

this incident is not like what some Japanese describe, “it is just a pure border dispute caused by unclear border line”, but a military attempt by Japan to enter the Soviet Union North. It was only because the Japanese army was trapped in the tenacious resistance of the Chinese battlefield in 1938 and the Soviet Union had a strong military defense force in the Far East that the Japanese army dared not launch an all-round war against the Soviet Union.