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Catholic Thought on the Moral Problem of War

by professor kenneth himes

The catholic church has thought about the moral dimension of war for a long time; the topic arose during the beginnings of the church in the apostolic period of the first century. Whether the church has also thought well during the subsequent two thousand years is a subject for debate. But there is now a long tradition of Catholic reflection on war and peace. Robert Drinan was a student of that heritage and it shaped his perspective on numerous policy debates.


For a tradition to be a living tradition it must have a “growing end.” While rooted in the past, it must engage the circumstances of the present. A living tradition permits not only the wisdom of the past to inform our response to the present, but also allows for the present to elicit development in the tradition as new settings and new questions are encountered.


During the first three centuries of Christianity there was a widespread sensibility that violence could not be reconciled with belief in the teaching and practice of Jesus. Still, there were pastoral problems to be addressed as converts to the new faith spread beyond the boundaries of Judaism and the region of Palestine. On occasion, a new convert to Christianity was a member of the Roman military, or held a position of civic administration and governance involving the employment or approval of violent force. Could such persons remain in their pre-conversion roles or must converts abandon earlier responsibilities? As time passed, various church leaders answered that question differently.


In the fourth century, as the emperor himself accepted Christian baptism and ever larger numbers followed his example, practical guidance for following the gospel led to new theories of what was, and was not, permissible for disciples of Jesus. As the growing Christian population moved from a socially marginal to a leading role in the empire, the topic of war was viewed in a new way. Within this changing context the doctrine of just war gradually evolved. Teachers such as Ambrose (d. 397) and then Augustine (d. 430) defended military action if it was undertaken with the proper attitude and in the right circumstances. Because of the prestige of Augustine, later Christian thinkers tended to adopt his view of war as analogous to a police action, punishing evildoers and protecting innocent people.


In subsequent centuries scholars such as Thomas Aquinas (d. 1274), Francisco de Vittoria (d. 1546) and Francisco Suarez (d.1617) further systematized Catholic thought on war. They developed theories that reflected the particular historical circumstances of their respective times, i.e., feudal rivalries, the presence of militant Islam, the rise of sovereign nation-states, and European expansion in the new world. The doctrine of just war, never far removed from the actual circumstances of the time, was formulated, questioned, reconsidered, and reformulated throughout the centuries. The rise of nation-states and modern weaponry compelled just war theorists to further extend and develop just war thinking if that tradition was to continue to guide the modern conscience.


Today, the emergence of a new context for just war thinking is forcing the tradition to once more undergo development. Among the elements of the new context are the diminishing threat of superpower nuclear war, the increasing incidence of conflict inspired by ethnic and religious differences, greater sensitivity to human rights abuses, the risks of terrorism, the ever stronger ties of interdependence, and the pressures both within and without territorial borders which recast traditional notions of state sovereignty.


At the center of the doctrine or teaching on just war stand three convictions: 1) violence, though always regrettable, is not inherently or necessarily a moral wrong; 2) the harm caused by war’s violence may be justified, at least in some cases, by an appeal to the good ends protected or obtained by war; and 3) the use of armed force within war is a rule-governed activity for even war is subject to ethical assessment and governance.


Catholic thought on these topics is characterized by a cautious optimism. In Catholic teaching, war is not inevitable and thus we can hope for the abolition of war. Tempering this hope is the understanding that, in a sinful world, conflict is unavoidable. Without deliberate and serious commitment to manage them, conflicts will evolve into the armed violence of war. Yet, even in war the moral dimension of human existence must not be ignored. There ought to be restraints upon both the judgment to go to war and the means whereby war is waged. Just war teaching was developed to articulate those restraints.


The categories of just war theory were the dominant form of discourse about war within Catholicism for centuries. The living tradition, however, has witnessed there-emergence of nonviolence as a legitimate alternative to just war thinking in Catholic circles. Of course, within Roman Catholicism there have always been supporters of non-violence who questioned the soundness of the just war position. Can Christian disciples countenance resorting to violence to achieve values such as justice and peace?


Catholic moral theology has never accorded peace the status of an absolute value.This is especially the case when peace is understood in a minimalist sense as being the absence of violence. Church teaching has traditionally maintained that such a minimal peace is not even a true peace. For, as Vatican II stated, peace requires more than “merely the absence of war.”


It may be common for people to think of peace as what happens once the guns cease to fire. Yet in the Bible the prophet Isaiah call peace “an enterprise of justice.” From this perspective, war is not the opposite of peace. Rather, the outbreak of armed violence may be understood as an effort to establish a true peace in a situation of injustice. It is not a contradiction, therefore, in Catholic moral theory to state that a just war can be fought to establish an authentic peace.


Modern church teaching has refined the biblical insight to insist on a particular form of justice—developmental justice—as the new name for peace. That is, the justice that is necessary for true peace is one that works to overcome those excessive inequalities among peoples that give rise to violent conflicts. In our time, this emphasis on justice as development brings a critical edge to the work of peace.


Finally, the most significant development in recent decades has been the reemergence of nonviolence and pacifism as a counterpoint to just war thinking on questions of conflict and peacemaking. Within the tradition it may be said that there is a particular kind of nonviolence that is acceptable. A pacifism that withdraws from society or denies obligations of securing justice for others is not possible, but a commitment to promote human rights and secure human dignity using nonviolent methods is endorsed by Catholic teaching. In sum, the present Catholic teaching is that both just war and pacifism must aspire to the same goal: establishing a true peace. Where there is a legitimate pluralism at the level of means, both armed force and nonviolence are judged to be permissible options for the conscientious Catholic.