How should Japan's foreign policy or role in the world be characterized? This question has been under discussion for some four decades, and answers have often been put in terms of 'power'. By using a new framework for analyzing foreign policy - what is called 'relational power analysis' - this article aims to offer a conceptually more coherent picture of Japan's foreign policy or role in the world in terms of power. It does so by assessing a 'litmus test' for Japan's foreign policy, namely the dispute with China over the Pinnacle (Diaoyu/Senkaku) Islands. In particular, the article analyses new materials on Japan's response to the Territorial Waters Law passed by China in 1992, which strongly reasserted China's claim to the islands. It concludes that Japan exerted power over China in regard to the issue and suggests that it did so using mostly civilian instruments along non-traditional dimensions, for example, positively and defensively. What is called 'ideational statecraft' - or attempts to exert influence relying primarily on the transmission of ideas, norms and symbols - is a part of the relational power framework, and it proves appropriate to the present analysis. Japan's ability to affect the PRC with such instruments, however, is helped by the fact that leading Chinese policy-makers prioritized economic development and modernization over sovereignty. The wider implication of such conclusions is the idea that Japan is a quiet but not silent power in world affairs.