This chapter is a concluding chapter. It summarises the cases examined in the book and tests the appropriateness of the book’s central argument. Previous chapters demonstrated that the weakening presence of the left since the mid-1990s and localisation of the international norm resulted in Japan’s enlarged military role. However, this shift in Japan’s security policy occurred in a way that did not violate the domestic norm. This implies that Japan’s decision-making process was loosely constrained by the domestic norm. However, a norm is not static, and the degree of localisation of the international norm continues to influence Japan’s security policy.