This article argues that Thomas Aquinas's virtue ethics approach to just war theory provides a solid ethical foundation for thinking about the problem of war. After briefly indicating some shortcomings of contemporary views of international justice, including pacifism, legalism, progressivism, realism, pragmatism, and consequentialism, the article examines Aquinas's question ?On War? in the Summa Theologiae. It then attempts to show that Aquinas's thinking on war is rooted in his understanding of the virtues by providing a brief overview of how the (...) cardinal virtues (prudence, justice, fortitude, temperance) and theological virtues (faith, hope, and charity) are connected to just war considerations. (shrink)