A well-known American social scientist ventures into a study of Japanese attitudes toward national security. He argues that the two main paradigms of American specialists in international relations -- realism and liberalism -- are insufficient because they disregard culturally conditioned "norms." Says the author, "Norms matter for national security policy," and "Contemporary Japan . . . eschews police and military violence." The book explores how these norms came about and concludes with a prediction that "Japan's security policy will continue to be shaped" by its domestic norms rather than by the international balance of power. If the argument was couched in more modest terms, for example that a nation's values shape its view of national security, few would disagree. But the author seems determined to throw overboard international relations specialists' emphasis on structural and situational determinants of state behavior. This is not very convincing. What if the United States and Japan end their security alliance? Or what if China becomes much more expansionist? Will these scenarios be completely irrelevant to how Japan defines its security "norms?"