The Japanese Imperialist Army had a poor reputation for counterinsurgency (COIN) in both theory and practice. In China, it is best known for perpetrating the Rape of Nanking, one of the worst atrocities committed against a civilian population in the 20th century (although it clearly faces stiff competition). When Chinese civilians provided some material aid to American air men who landed in China after executing the Doolittle Raid on Tokyo, the Japanese army retaliated by killing as many as 250,000 Chinese civilians. The notorious Unit 731 tested chemical and biological weapons on Chinese civilians during the war.
Japanese policies helped alienate potentially cooperative anti-colonialists in Malaya, the Philippines, the Dutch East Indies, and elsewhere.In Malaya, Japanese soldiers with a limited understanding of Islam attempted to force Muslims to pray towards Tokyo instead of Mecca. While the Japanese Army had some success in the DEI and along the Indian border, the overall impression is of an organization with little capacity for and far less interest in counter-insurgency policy.
However, in a chapter in the recent volume Hybrid Warfare, retired Japan Ground Self-Defense Force (GSDF) Lieutenant General Noboru Yamaguchi argues that the Japanese Army took COIN theory far more seriously than is commonly believed. Yamaguchi argues that the Japanese Army identified Communist Chinese guerillas as the central threat in North China, largely because of its feared that these formations could threaten Kwantung Army logistics during a war with the Soviet Union.
Yamaguchi quotes a Japanese staff officer as arguing:
"Promotion of local security and improvement of people’s lives have a [reciprocal] cause-and-effect relationship. As an area becomes after step by step, the life of the local population can be improved. Only under a situation where local security is achieved can inhabitants have jobs that will build their economy. If their life is improved and stable, nobody would want to become the vermin of the community except for determined insurgents who are a deviant minority among the people."
The reference to “vermin” aside, this would not be out of place in modern U.S. COIN literature. Yamaguchi suggests that elements of the Japanese Army and a variety of hybrid civil-military organizations took the problem of COIN quite seriously from a strategic point of view, appreciating that the only way to victory in China was the establishment of a self-sustaining, pro-Japanese Chinese government.
However, the Japanese Army suffered from problems of focus and resources. Rather than concentrating on counter-insurgency operations, the Army needed to prepare for conventional operations against Chiang Kai Shek’s Nationalist Army, defensive operations in jungle and island theatres against British and American forces, and finally the long-anticipated Soviet invasion of Manchuria. These threats all posed radically different challenges, making training haphazard and incoherent. The Japanese also faced unity of effort challenges, with civilian and military agencies organized around pacification and institution building losing out in intra-agency battles against conventionally oriented officers.
In the end, regardless of the intentions some Japanese may have had towards winning a COIN victory in China, the odds against Tokyo were just too steep to overcome. Japan directed its strategic and military attention toward other, more pressing matters, leaving the various units and agencies tasked with COIN rudderless and under-resourced. The policy responses were often horrific; with no useful tools for managing the insurgency, Japanese units resorted to increasingly brutal tactics in a desperate attempt to enforce order, tactics which did little more than inspire greater support for insurgents.
In Iraq and Afghanistan, the United States has found the practice of COIN bewilderingly difficult. The Japanese experience suggests that while many of the basic theoretical precepts of insurgency management are easy to grasp, execution is devilishly hard. U.S. success has been limited in the best of circumstances. In less ideal circumstances, Japanese practice quickly devolved into atrocity.