This work investigates the legal boundaries and prohibitions surrounding the use of force by sovereign states within the framework of international law. Professor Ian Brownlie, a distinguished scholar in the field, provides a rigorous historical analysis of how legal norms have evolved to restrict military aggression. By synthesizing the deliberations of the League of Nations and the United Nations, the text establishes a comprehensive framework for understanding the legality of state-sanctioned force.

Experts and legal scholars consistently identify this work as a foundational text for understanding the development of international law regarding state force. Readers frequently note the academic density of the prose and the meticulous attention to historical documentation provided by the author.