Natural law, in the Augustinian and Thomist sense, reflects not merely man’s nature as it is, but as it should be, accounting for the moral aspirations and moral instincts they believed were natural to man’s being. Natural law requires us to live justly: to live well in society, with love towards one another. What does it mean to love our neighbors politically? It means to live and govern in accordance with the “tranquility of order.” Responsibility for upholding this kind of peace is what “sovereignty” meant in the Augustinian era. Peace is not merely the absence of violence, but the presence of the conditions that enable flourishing. Just war is war that accords with justice: it is authorized political violence required to uphold love-directed justice. War is an instrument for defending and sustaining the tranquility of order, understood as an act of love for our neighbors and our enemies alike. With this framework, Augustinian thinkers generally favored humanitarian and state building interventions: military operations to protect the innocent, stop war crimes or crimes against humanity, punish tyrants and war criminals, and foster conditions of lasting peace and stability.