Prior to World War II the Japanese imperial army and navy lived a cat-and-dog existence. They individually reported to the emperor and there was no organization to coordinate their efforts. Their perceived threats and strategies were also different. The army had traditionally looked north toward Russia while the navy focused on America, especially after the Russo-Japanese War. Both services maneuvered for larger shares of the budget. Even war did not bring them closer together. The navy never informed the army of its crushing defeat at Midway, and the army was preparing to build its own submarines by the end of the war because it did not trust the navy.
After the conflict Japan drew from experience and established the self defense force (SDF). The National Defense Academy, established in 1953, adopted a joint education system. The joint staff council coordinated ground, maritime, and air staff offices. Joint training included command post exercises, maritime transportation of ground forces, and maritime and air exercises. A central procurement office managed acquisition for ground, maritime, and air self defense forces.
Not all the lessons of the interwar period and World War II were thoroughly learned. Jointness among the services was not fully developed. Threat perceptions and strategies still differed. The ground self defense force (GSDF) continued to primarily look north, while the maritime self defense force (MSDF) tended to focus on sea lines of communication, extending southeast and southwest from Japan. Each service built its own communication system, target symbols, and message formats. As a result, they could not communicate among themselves on common secure voice devices. The air self defense force (ASDF) did not share any early warning information from E2Cs, originally a U.S. Navy aircraft, with MSDF ships afloat. The ASDF data link system was incompatible with the MSDF data link 11. The services literally had their own languages; for example, coastal areas were the beach to GSDF and the surf to MSDF.
Recent efforts to improve jointness in the Japanese self defense forces offer an opportunity to look ahead and identify ways that these initiatives can contribute to combined operations.
Renewal of Purpose
Jointness problems are being resolved for several reasons. First, Japan's security partner, the United States, has stressed integrated operations since passage of the Goldwater-Nichols Act in 1986. Because each service maintains high levels of interoperability with its American counterpart, especially MSDF, many joint assets such as a tactical command and control system and message text format have been introduced. Consequently, every service exchanges messages using a common format. Both MSDF Aegis destroyers and ASDF airborne warning and control system (AWACS) aircraft are equipped with the U.S. joint tactical data link system, allowing the services to establish data communication with each other. If Japan deploys ballistic missile defense, which is currently under study, jointness among the SDF services will advance further in terms of command, control, communications, computers, intelligence, surveillance, and reconnaissance because such defenses will require integrating AWACS aircraft, Aegis platforms, Patriot missiles, and other assets.
Second, the services have begun to tackle similar issues, which was not always the case during the Cold War. The new defense guidelines adopted by Japan and the United States also have led to a common perception by all the services of potential threats to the region.
Third, the legal basis for jointness within SDF has improved. The joint staff now has more authority and responsibility. For example, amendments to the defense agency establishment law, enacted in March 1999, have resulted in improvements in coordination of SDF components when the need arises for integrated operations in response to a crisis such as large-scale disasters. …