James D Llewelyn 
Japan’s Evolving Notion of National Security [PDF ebook] 

This book examines the incremental changes that have occurred in Japan’s national security considerations and policies over the last 60 years. It uses a careful collation and synthesis of a number of key ideas and concepts from some of the most influential Japanese scholars of the last half century, as well as referring to a number of more recent scholars who have made some interesting contributions to the Japanese security debate.