「帝国国防方針」政戦略考

The past studies of Japan's Imperial Defense Policy (IDP) of 1907 point out that the IDP contains a number of both theoretical and practical problems. They may be aptly summed up in the following outlines: (1) Did Japan's national strategy match its grand military strategy? (2) Was there proper coordination between army and naval strategies? (3) Did force requirements and availability match the strategy?<br>In this article, the author argues that the most fundamental question at issue is sound coordination between national strategy and military strategy. He then tries to probe into the consensus-building process between the government and the military.<br>By establishing the IDP Giichi Tanaka wanted to find strong justification for continued military expansion and the maintenance of a high level of military preparedness following the termination of the Russo-Japanese War. For that purpose, he needed to demonstrate the matching of national strategy and military strategy and to establish proper coordination between army and naval strategies.<br>Prior to the establishment of the IDP, Meiji political leaders had launched a “northward” advance by changing their traditional national strategy of hokushu nanshin or “defend the north, advance to the south”. However, this did not mean that the government had given up the “southward advance” strategy, but it simply wanted to maintain a noncommittal attitude toward changing the fundamental national strategy.<br>Under these circumstances, Meiji Japan's postwar military leaders took the initiative for expended interpretation and laid down the fundamentals of the nanboku heishin national strategy or “concurrent advance both to the north and the south” as the basis for the IDP. Subsequently the “overseas” offensive strategy was established, comprising the continental offensive strategy and the naval offensive strategy. This eventually led to the grand military designs of maintaining 50 divisions in wartime and of establishing the ambitious 8:8 Naval Ratio.<br>It would be taken for granted that the agreement between politico-military leaders is a precondition for the setting of the national strategy. But, in the case of the IDP, there was no prior consultation between the government and military leaders, and the military will was simply imposed on the prime minister, thus completely disrupting the traditional consensus-building process.<br>This fundamental lack of coordination between the government and the military had an inherent danger of drifting Japan on a future collision course to fight a full-scale war with all the world powers.