HONOLULU -- Taro Aso's recent comment in plain words about the "threat" posed by China's military modernization effort is as remarkable as the supposed threat itself. The readiness of a Japanese Cabinet official, and a foreign minister no less, to publicly acknowledge and criticize China's military buildup marks a profound departure from past practice.

His comment underscores the fact that two processes are occurring simultaneously in East Asia -- the "rise of China" and the evolution of Japanese security policy. These changes are pushing Asia into uncharted territory. Never before has the region had to accommodate two "rising powers" at the same time.

Development has stoked understandable and justifiable pride in China, fueling both a heady nationalism and a defense modernization effort that unnerves many foreign observers. Seventeen years of double-digit defense spending increases, steady expansion of ballistic-missile inventories, nuclear-weapons development, and the pursuit of a blue-water navy all appear disproportionate to any security threat that China may face.