Just war theory and the concept of warfare have been framed and examined by numerous philosophers, political theorists and theologians since the Roman era with many having a major influence on the way in which the moralities of war are considered. Two of the earliest theorists could be argued to have had the largest and most enduring impact on the notion of just war having developed the concept through their writings. Those theorists are Marcus Tullius Cicero, an early Roman philosopher, and Augustine of Hippo, who was an influential figure in the development of Christianity some 400 years later. In order to fully understand the concept of just war, it is necessary to examine the arguments of both men and compare them to note how the concept progressed as times changed. As such, this essay will examine the concepts of just war and warfare in the works of Cicero and Augustine with a view to arguing that firstly, although both could be deemed pacifists who were basically concerned with the morality of war, Augustine’s theory of just war was more developed than Cicero’s. Secondly, it will argue that the fundamentals of the theories espoused by both men differed as a result of the changes in both the political climate and nature of Christianity.
The methodology that will be used in order to prove the thesis statement outlined above entails examining the primary texts of Cicero and Augustine and offering analysis of the points made by both men individually before closely comparing the theoretical definition and perspective of each argument. In addition, secondary texts will be used to reinforce the relevant points that are made in relation to the concepts of just war and warfare. It will be necessary to examine a number of critical perspectives in order to present a rounded argument so the use of a comprehensive bibliography will be applied.
According to Adeney, Cicero was the architect of the first concept of just war that was both comprehensive and broadly designed to apply to the moral circumstances of all wars  . As such, the points that he made in relation to war could be described as relatively unique. Whereas warfare had been used extensively in the past for the slightest perceived ill, Cicero offered the following assertion to weave a thread of morality into the concept: “…no just war can be waged except for the purpose of punishment or repelling enemies… the only excuse… for going to war if that we may live in peace unharmed.”  In effect, this quote from Cicero suggests that the state is important to the notion of just war or, more specifically, protecting the interests of the state and therefore Rome. Although morality does seem to be a part of this particular theory, there does seem to be a question as to whether it is universal morality or that divined by Roman law. However, the fact that a just war would assure long term peace implies that the concept should be used for a degree of protection. Given the political instability of the era and the continuous state of war  , it stands to reason that Cicero would advocate a just war in the interests of achieving peace on a long term basis.
Augustine, on the other hand, offers the following definition for just warfare: “As a rule just wars are defined as those which avenge injuries, if some nation or state against whom one is waging war has neglected to punish a wrong committed by its citizens, or to return something that was wrongfully taken.”  This effectively summarises the coherent and concise concept of just war that Augustine developed based on not only the theory that Cicero had previously espoused but also his strong Christian faith. As per the quote, Augustine’s concept of just war therefore had three specific facets – firstly occurring for a just reason that is unrelated to either power or personal gain, secondly as a result of a resolution based on authority invested in the state, and thirdly that the motive is never lost no matter how violent war actually is  . These practical points were supposed to define the moral debate that was to take place prior to any declaration of war to ensure that it was not only justified but also featured a strong detachment from any form of greed, selfishness and hatred. In effect, it was to keep war as a neutral solution that was a last resort. Augustine also stressed the need to achieve peace as a result of war rather than attempting to apply Christian pacifism impractically to a situation that indeed merited a war on moral grounds  . As such, he addressed both entering into war without just cause and neglecting to enter into war as a result of a misguided concept that could ultimately jeopardise security. Furthermore, he asserted the need to keep sight of goals in a political context to ensure that any war remained just throughout  .
The definitions of the concept of just war as espoused by Cicero and Augustine demonstrate differences that are immediately obvious in some areas, thus distinguishing them from each other. For example, Augustine’s criteria for a just war is based on three distinct principles, all of which have to be fulfilled in order to ensure that there is a fundamental basis in morality  . As a result of his Christian beliefs, the normative Christian tradition  and disapproval of immoral actions on the part of those seeking power, Augustine was able to focus on the morality of war in terms of state defence and religious principles. On the other hand, Cicero actively based his theory of just war on the need for justice. For example, Moreno-Riano’s interpretation of his theory declared the following: “Justice should circumscribe the basis of any war, and the most just war seems to be that which is provoked by the injustice of the offending party.”  However, this is a particularly broad definition and therein lays a major weakness of Cicero’s argument as compared to that of Augustine. The perception of injustice had no particular criteria to fulfil: “Of injustice there are two kinds, – one, that of those who inflict injury; the other, that of those who do not, if they can, repel injury from those on whom it is inflicted.”  Therefore any invading force would be able to claim injustice based on any well argued platform related to the notion of injustice regardless of the morality underlying the claim made.
Another major fundamental difference in the concepts of just war espoused by Cicero and Augustine lies in the credence given to political power. According to Augustine’s theory of just war, religious justification must be reconciled with state interests in order to form a solid foundation of a just war: “For Augustine, the desire of Christians to be faithful to the Christian message of nonviolence had to be reconciled with the need for a state to base its defence on loyal and obedient citizens.”  This ethical political stance could be said to be based on Christian values but in actual fact it is a practical formula that every war could be based upon. It is therefore far more comprehensive and, according to Regan, morally correct than Cicero’s theory because the “…particulars of Cicero’s explanation of just war are less important than the fact that he required war to be somehow justified.”  Steffen reinforces this particular point by highlighting the fact that Cicero takes Roman law to be the only form of moral guidance  . By basing his concept of just war on one political philosophy, especially one that is biased towards self interest, undermines the scope of the theory itself and leaves it open to exploitation as well as criticism. For example, Lackey advocates that: “It is clear that Augustine enlarged the scope of just wars far beyond the limits envisioned by Cicero. According to Cicero, a war is just if it repels an injury; according to Augustine a war is just if it is a struggle against sin.”  By acknowledging that the scope of both concepts is different, it is easy to see how the nature of religion and indeed the political climate were able to make such an impact on how just war was not only framed but also used.
In conclusion, there can be little doubt that both Cicero and Augustine were instrumental in developing the theory of just war and the criteria any individual or collective would need to meet in order to ensure that they were indeed justified in going to war. However, similarly, there can be little doubt that there are fundamental differences in the concepts that each developed, thus ensuring that they are easy to distinguish. Cicero’s argument for just war does have fundamental weaknesses that are based on not only self interest but also a distinct belief that the Roman way was the only way. As such, he was undoubtedly influenced by the political climate. Augustine, on the other hand, was influenced by political and religious factors and balanced the two. As a result, his argument was far more developed, coherent and logical than his predecessor. Despite the fact that the two are fundamentally different, though, both are instrumental in developing the concept of just war and developing the notion of warfare based on morality.