"Since the late 1990s, and particularly since 2000, the U.S.-Japan alliance has undergone significant changes. During the first term of the Bush Administration, converging U.S. and Japanese objectives in confronting North Korea's nuclear and missile programs and Japan's participation in U.S. operations in Iraq and Afghanistan reinforced the notion of the U.S.-Japan alliance as one of the central partnerships of U.S. foreign policy, particularly in Asia. [...]. After a brief historical review, this report examines policy changes that have driven actual and proposed shifts in the alliance. Key features of the proposals include a reduction in the number of U.S. Marines in Japan, the relocation of a controversial Marine air base in Okinawa, expanded cooperation in training and intelligence sharing, and command structure changes. The proposed changes would create new roles and missions in the alliance, with an emphasis on interoperability, joint missile defense, and more Japanese participation in international operations. Some of the most prominent operational, budgetary, legal, and societal challenges to upgrading the alliance are discussed in this report. The dynamic nature of the alliance and the strategic environment in northeast Asia present a number of challenges for U.S. policy, including containing North Korea's nuclear ambitions, dealing with a rising China, sustaining political alignment with Tokyo, managing the U.S.-South Korea relationship, and considering the nuclear future of the region. The report concludes with a number of potential options for U.S. policymakers to protect U.S. security interests in the Asia Pacific."
CRS Report for Congress, RL33740