Book excerpt: The author explores the changing nature of Japanese security policy and the impact of those changes on the U.S.-Japan security alliance. He begins his analysis by acquainting the reader with an insider's view of the conflicted Japanese conceptions of security policy and the various ideational and structural restraints on expanding the role of the military. Next, he explores the events of the past decade that have caused huge shifts in security policy and posture and predicts the future vectors of those changes within Japan. Finally, the author overlays the likely Japanese security future on the alliance and concludes that changes in the basic relationship between the United States and Japan must occur if the alliance is to retain its centrality 20 years from now.