Note 3 — Opinion of the Augustinians

The second condition of righteous war is that the cause for which it is waged shall be a just one, as St. Thomas says: “Those upon whom war is waged deserve it for the offenses that they have committed, and the grievances that they have inflicted upon the one who makes war on them.” Thus says St. Augustine (lib. 83. Quæstionum super Josue, 9. 10), and Gratian quotes him (23, q. 2, c. Dominus noster): Justa autem bella solent definiri quæ ulciscuntur injurias, si gens vel civitas plectenda est, quod vel vindicare neglexerit quod a suis improbe factum est, vel reddere quod per injuriam ablatum est.3 And as this injury and grievance may be of many kinds, so too, many and various are the just causes of war; but we will consider here only those which make for the matter in hand, confirmed by the authority of Scripture.