This book studies national security strategies introduced by the Koizumi administration (2001–2006) and the second Abe administration (2012–2020). Drawing on the common themes of ‘normalization’, constitutional revision, in particular Article 9, and the right of collective self-defence, the volume examines through the theory of neoclassical realism how and why the national security initiatives of the two administrations are different in their extent of normalization of Japan. It shows how the policies were influenced by the respective Prime Ministers who responded to the international environment surrounding Japan during their tenure and were also shaped by internal concerns.The volume will be of great interest to scholars and researchers of Asian studies, politics and international relations.