Book introduction

　This book addresses the growing phenomenon of consent-based use of force, in which a state permits another state to use force within its territory. Despite their increasing prevalence—particularly in civil wars or counterterrorism operations—the theoretical basis for their justification remains underexplored, especially given the peremptory nature of the principle of non-use of force. Practical questions—the conditions under which consent can justify the use of force—also remain unresolved.　　
　While previous studies have treated theoretical and practical issues in isolation, this book presents an integrated framework for addressing both. It does so by supplementing the traditional “inter-state” understanding of the principle of non-use of force with a human-oriented perspective. In doing so, the book not only seeks to reconcile theory and practice concerning consent-based use of force, but also contributes to the broader humanization of international law by rethinking the relationship between state, use of force, and humanity.