Abstract
The International Politics of Datalink: Prescribing Japan's Policy for AllianceManagementMATSUMURA, Masahiro., Momoyama Gakuin University

Under the current Revolution in Military Affairs (RMA), connectivity incommunications and computers, or datalink, is of the central importance formultinational coalition operation in which the United States exercises leadershipover allied forces. Datalink is essential for automatic and high-speed -- quite often
real-time or near real-time, processing of tactical data in command, control,communications, computers, intelligence, surveillance, and reconnaissance(C4ISR). This study places its analytical focus on assessing datalink capabilities ofU.S. and allied forces and investigating limits as well as opportunities for coalition
operation, in an effort to prescribe specific policies designed to retain Japan's
military autonomy and political independence.
The capability gap in datalink between the U.S. and major allies has increasingly
widened. Allies have suffered from rapidly shrinking defense budgets and areunable to catch up the U.S. which continues aggressive investment in achieving
military transformation. Thus the U.S. faces a dilemma in choosing unilateral ormultilateral military action, in search of an optimal combination of militaryeffectiveness and efficiency with legitimacy and burden-sharing. To manage thisdilemma, the U.S. needs to promote and assist cost-averse allies in enhancing
their datalink capability.
This study emphasizes the critical significance of tactical data distribution
essential for command & control, weapon- and fire-control, particularly Link-16,
in context of the historical evolution of various Links and the current datalink
capabilities at the platform level as contrasted with doubtful near-future upgradeplans. The analysis reveals emerging divergence of policy priorities of the U.S.
and allies as a resultant of their different military doctrines and the cumulative
effects of investment required to implement such doctrines, which mutuallyreinforce.

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In addition to the above affordability factor, this work also stresses the core natureof releasability, or transfer of black-box technologies in codevelopment projects,
particularly encryption measures. The examination highlights the Multifunctional
Information Distribution System (MIDS) project in which major European allies
are U.S. partners and the Cooperative Engagement Capability (CEC) project inwhich the U.K is an only U.S. partner, while exploring a possibility of applying theAnglo- American model to the U.S.-Japan alliance. It is contended that Japanneeds to exercise its own encryption measures on U.S.-made or U.S.-designed
Link-16 equipments, or JTIDS (Joint Tactical Information Distribution System),
MIDS, or their derivatives.
Given the affordability and releasablity factors, this study identifies major sourcesof potential bilateral conflicts in alliance management. It is urged, at the initial
phase efforts, to sequentially execute upgrading Japan ﾕ s datalink capability as
common interest, in which the three services of the Self-Defense Forces establish
joint connectivity via Link-11, a legacy system, and a unified SDF command fortheater missile defense, while postponing a full-scale acquisition of the U.S.
standard datalink system, Link-16, on the commercial off-the-shelf basis. Whenthese conditions are met, Japan is urged to negotiate for concluding a General
Security of Military Information Agreement (GSOMIA) with the U.S. and thereby
to bargain for necessary technology transfers from the U.S., especiallyinformation related to Link-16 ﾕ s encryption. Depending on near-future choices of
their policies, the U.S. and Japan may strengthen bilateral alliance or significantly
reduce its viability.
Kokusai Anzenhosho [Journal of International Security] Vol. 31, No. 3 (December
2003), pp. 17-37.

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