Japan again.

Japan Rising: The Resurgence of Japanese Power and Purpose, by Kenneth B. Pyle (PublicAffairs, 448 pp., $29.95)

KENNETH PYLE, the dean of American Japan hands, has written this book at a critical juncture in Asian international relations. Tokyo is intensely debating its strategic future, as its neighbors and its key ally in Washington watch with interest and some apprehension. Tokyo's resurgence is replete with contradictions. For example, Japan has embraced the promotion of universal values as a core component of its foreign policy--yet it is willing to endure international condemnation for denying that it forced women to become sex slaves during World War II. Japan has been pacifist for 60 years, but is still regarded as militaristic by much of Asia. Pyle's book helps explain the massive turnabouts that Japan has made in its foreign policy over the past century, and why Japan's neighbors regard its recent foreign-policy readjustment with a measure of suspicion.

Pyle builds his thesis around a pair of central propositions: First, Japan is and always has been "realist" in its orientation, seeking to expand its influence and power at every turn. And second, Japan shapes and reshapes its domestic institutions to carry out its realist foreign policy. Thus, when the Sino-centric order was breaking down--to be replaced by Western imperialism --the Meiji Restoration allowed Japan to adopt the Western technology, institutions, and practices that would secure Japan's rightful place in the regional hierarchy. This effort culminated in Japan's victories in the Sino-Japanese and Russo-Japanese wars, which allowed Tokyo to distance itself from the Asian powers it had surpassed and ally with Great Britain, the hegemon at the time.

As Anglo-American international liberalism replaced the imperialist system that broke down during World War I, the Japanese tried to adjust. But, as Tokyo concluded that the real purpose of the new order was to contain Japan's ambitions, and as the great powers failed to enforce the new system anyway, Japan saw the opportunity to increase its influence in continental Asia. As liberalism broke down entirely and the world descended into a Nazi-led "New World Order," Japan followed suit, instituting militaristic and fascistic domestic institutions to support an imperialist foreign policy throughout Asia.

During the Cold War, Japan reconstituted itself as the "Venice of Asia": eschewing military force (taking advantage of the security guarantee provided by the United States) and reshaping its domestic institutions in line with a policy of state-guided economic growth. After years of sustained economic growth, this policy reached its apex in the 1980s, when such proud Japanese nationalists as Sony's Akio Morita announced to the world that Japan's model of economic growth was superior to America's.

The post-Cold War period was defined by uncertainty and flux in Asia. Japan was at a loss, with no defining regional order from which to take its cues, and fell into a period of economic stagnation and a crisis of confidence. But the rise of Chinese power and North Korea's reckless militarism provided the impetus for Tokyo to reform yet again. Japan elected a charismatic prime minister in Junichiro Koizumi, who implemented wide-ranging domestic and foreign-policy reforms.

Domestically, Koizumi declared war against Japan's factional system of politics, as well as the bureaucracy's grip on policy. These moves allowed him greater flexibility to reshape foreign policy in a pro-American direction. Koizumi dispatched logistic and support vessels to back the U.S. effort in Afghanistan, and subsequently deployed reconstruction troops to Iraq. He initiated a debate about changing Japan's pacifist constitution, and entered an agreement for ballistic-missile cooperation with the U.S. that will ultimately necessitate lifting the Japanese ban on collective self-defense.

In short, Koizumi restored honor to a depressed Japan after a decade of economic doldrums, political stagnation, and international-relations embarrassment. Perhaps even more significant, Koizumi signed Japan on to a global agenda with the United States that includes democracy promotion. Embracing universal democratic values is a serious departure from foreign-policy practice for Japan, a country that Pyle argues never had a sense of universal values, and always followed a narrow definition of its self-interest.

There are some unresolved tensions in Pyle's book. For example, his heavy reliance on international-relations theorists' definitions of "realism" renders this a term without much meaning. How can it be realist for Tokyo to attack America in World War II, knowing it will almost certainly be defeated, and realist for Tokyo to eschew military force altogether and rely completely on others for its defense? It is more accurate to describe Japan as a country that assesses its strategic environment and then opportunistically presses its position as far it can go-sometimes with disastrous consequences, as in World War II, and sometimes triumphantly, as in the Cold War. Attempting to shoehorn this behavior into a theoretical framework oversimplifies Japanese strategic behavior.

The other unresolved question the book poses is about the nature and effects of Japan's cultural identity. Pyle argues that, in each period, Japan's adaptation of others'values and practices came at the cost of national and cultural pride. Wounded pride certainly explains some of Japan's strange behavior, such as pursuing a policy of continental dominance and attempting to throw the British and Americans out of Asia. But is there an immutable Japanese national and cultural identity that chafes under elite policymaking, in sometimes suicidal ways--and if so, is this really the source of Japanese foreign policy? If the answer to these questions is yes, then Pyle's thesis about Japanese "realism" is wrong. (A "realist" Japan would be motivated to reform and resurge in response to China's rise--the classic realist attitude that focuses on fear and security.)

Pyle is at his best in describing the shrewd prime minister Shigeru Yoshida, whose post--World War II strategy guided Japan until the Soviet Union fell. Yoshida was so determined to minimize Japan's international-security commitments that he secretly prodded the Japanese Left to stir up unrest when Secretary of State John Foster Dulles visited to press his vision of an Asian NATO. Don't push us too far, Yoshida was saying, or we might not be the center of power countering Soviet expansionism that you wish us to be.

As Pyle points out, Yoshida's strategy may have benefited Japan at the time--it had no collective-security obligations, and could focus on becoming an economic powerhouse. But the absence of a NATO-style collective-security organization in Asia today is dangerous. There is no strong organization with a shared sense of values and purposes to mediate outstanding territorial issues, work out ways to share resources, or soothe historical grievances. Regional forums have become battlegrounds for Sino-Japanese, Sino-American, or Japanese-South Korean competition.

Meanwhile, as the global economic and strategic center of gravity has shifted to Asia, American policy has not kept up. Pyle asserts that the relationships between China, the U.S., and Japan (I would add India) will shape Asia's future in accord with two major trends. The first is increased economic growth and integration, technological dynamism, and the growth of regional forums; the second is a competition for influence and power against a backdrop of historical animosities and unsettled territorial claims, all in the absence of strong, integrating institutions. Which trend triumphs depends in large measure on continued U.S. hegemony in the region: Left to their own devices, the Asian powers will operate in a competitive Hobbesian world of "self-help," the outcome of which could be disastrous. U.S. leadership will be necessary to build a region where the powers cooperate to promote security, economic development, and human rights.

Washington's policy goals in Asia make its recent refusal to accept a Japanese proposal for a regional democracy forum all the more counterproductive. Japan is actually taking the lead in articulating a positive strategic vision--and, very uncharacteristically, a vision based on universal values. As in Europe, a democratic alliance has a better chance of enduring than the alphabet soup of institutions that currently exist. Unless and until a collective-security organization is formed, Pyle stresses, Washington's hegemonic presence will be needed to ensure free and open trade, promote democracy, and make sure no dominant Asian power emerges to undo a peaceful and prosperous regional order. Since Japan will be crucial to Washington's continued preeminence in the region, policymakers should be as attentive to the trials and tribulations of Japan's rise as they are to China's. Pyle provides us with some needed context, as Japan continues to find its way.

Mr. Blumenthal is resident fellow in Asian studies at the American Enterprise Institute.