Along with other classics like "Normalizing Japan," "Koizumi Diplomacy," and "Client State," this is easily one of the best books on Japan's security policy.
What distinguishes this book is its attention to historical details and its argument for the "Goldilocks" tendency in security affairs -- for Japan to be neither too hot, nor too cold in balancing the many relationships necessary to maintain security. While Japan will continue to hug the US tightly, modernize its military, and expand the power of the JSDF through ad hoc legislation, it will also look to engage its neighbors through multilateral diplomacy and institutional building.
Samuels argues that Japanese leaders were persistent rather than reluctant realists (p. 189), and that pacifism never played a dominant role in foreign policy making. Japan has always been realist, even if this realism is often expressed in contradictory terms. As Samuels states, hedging is a natural part of any realist grand strategy: “Since 1957, when the Ministry of Foreign Affairs issued its first postwar diplomatic blue book, every formal statement of Japanese grand strategy has articulated mutually inconsistent goals” (p. 198-199). The co-existence of both an Asian-led economic community with a US-led defense community has clear advantages for Japan. Japan would be able to balance against the US and European powers with its economic power and China with its military power (200). Samuels suggests the Japanese have never been more democratic and more open about their defense policy debates than they are today (196)—the nature of democracies tends to be self-correcting.
One of the most important insights of the book is the Japanese sensitivity to costs of defense. Even after the 1976 NDPO and the 1995 NDPO when the sanctity of the alliance was reaffirmed, the number of ground troops, surface ships, and fighters were all reduced.
Though the book is now almost seven years old, many of its insights remain important today. What will Japan do in security affairs? It will hedge and balance: It will embrace the US, while extending security assistance to other Asian partners; It will balance the need for national self-esteem with the need to assuage the historical sensitivities of its neighbors; it will modernize its defense force with a close eye on the need for fiscal discipline in the shadow of ballooning government debt. In the many contradictions of Japan's defense posture we will also see a well-balanced form of realism.