While Michael Walzer's distinction between preemptive and preventive wars offers important categories for current reflection upon the Bush Doctrine and the invasion of Iraq, it is often treated as a modern distinction without antecedent in the classical Christian just war tradition. This paper argues to the contrary that within Augustine's corpus there are passages in which he speaks about the use of violence in situations that we would classify today as preemptive and preventive military action. While I do not claim (...) that Augustine makes an explicit distinction between the two types of war (such would be anachronistic), I will argue that based on examinations of "De libero arbitrio" I.v.11-12 and "De civitate Dei" I.30 Augustine's discussions of hypothetical cases or actual wars in history provide insights helpful for contemporary reflection on preemptive and preventive wars. (shrink)