This book argues that since the end of the Cold War an international community of liberal states has crystallised within the broader international society of sovereign states. Significantly, this international community has demonstrated a tendency to deny non-liberal states their previously held sovereign right to non-intervention. Instead, the international community considers only those states that demonstrate respect for liberal democratic standards to be sovereign equals. Indeed the international community, motivated by the theory that international peace and security can only be achieved in a world composed exclusively of liberal states, has engaged in a sustained campaign to promote its liberal values to non-liberal states. This campaign has had (and continues to have) a profound impact upon the structure and content of international law. In light of this, this book deploys the concepts of the international society and the international community in order to construct an explanatory framework that can enable us to better understand recent changes to the political and legal structure of the world order and why violations of international peace and security occur.