The Clinton Administration and the 103rd Congress are in the early stages of a major review of U.S. trade, international and security relations with Japan, the principal U.S. ally and trading partner in Asia. A number of recent developments have raised tensions in this mutually beneficial relationship, which is still characterized by deepening economic interdependence and close political and security cooperation. These include the end of the Cold War, which has eliminated a common military threat; the recent renewed rise in Japan's trade surplus after several years of decline; and increasing international assertiveness by Japan, sometimes in conflict with U.S. policy.