Epistemic Implications of St. Thomas Aquinas’ Just War Theory on Global Peace ()
1. Introduction
Conflict is inevitable in any human society. The evolution of human history is characterized by conflict and antagonism. According to Francis O. C. Njoku, “what constitute reality in this area is human deliberations, choices or voluntary actions. If human intentions, pursuits and goals are the building blocks of socio-political reality, we must then admit that there must be frictions in forms of disputes and conflicts” (Njoku, 2014) . Conflict, dispute or clash of interest among people and nations in this 21st century have given rise to many crises ranging from political instability, religious violence, terrorism, and wars in many parts of the globe. War is the antecedent condition of human action. The human race has experienced many wars in history. Even today the whole world is engrossed in conflict and war. Hence, war is an inescapable fact of human experience. In the words of Sigmund Freud, “regardless of nurturing—no matter how peaceful the intentions of family, society or country, humans will still need an ‘outlet’ of their inborn … ‘instinctive’ aggressiveness” (Weeks, 2010) .
Nevertheless, war is geared towards peace. The intersection of war and peace is a perennial problem in the history of philosophy. One may begin to wonder how war that is characterized with devastation of human lives, properties and civilization can bring about peace. However, there is an adage that says “if you want peace, you must prepare for war”. So, War may serve a good purpose like ending the terrorism of unjust aggressors. In Nigeria for instance, the violence activities of Fulani herdsmen require counter violence for peaceful co-existence. In addition, war can also serve as an extreme means of resolving conflicts between parties or nation states. For example, the atomic bomb dropped in the city of Hiroshima and Nagasaki brought to an end of the Second World War. Some philosophers or scholars like W. H. F. Hegel see war as a crucial or determinant factor directing the course of history. Hence, he conceives war as “part of necessary means to maintain the substantive individuality and duty of sovereignty of the state” (Njoku, 2014) . In his own view, war is essential in a nation’s growth as it asserts itself in history. Thus, war can serve religious, political, military and economic interest of a nation.
Although war may have a good purpose like pursuit of justice (Eboh, 2005) or readdressing the violation of right of citizens etc., war in itself is bad which has devastating effects on human lives, culture, and civilization. The issue of moral justification of war comes into play. Is war ever morally justifiable given the fact of heinous or devastating effects of war on human lives, culture and civilization? Thus, Immanuel Kant remarked that “the greatest evils which oppress civilized nations are the result of war”. In determining the moral justification of war, two important concepts come into being Jus ad bellum-right to go war and Jus in bello-right conduct in war.
The jus ad bellum-right to go war deals with the notion of war having a just cause. In other words, it addresses the right to go war. Hence, it deals with the morality of going to war (Wikipedia Contributors, 2020) i.e. the rationale of embarking on just war. In this regard, war is conceived as an act of self-defense. For instance, everybody has the obligation to defend him/herself. So, if an aggressor declares war or violence on me, do I fold my arms and allow him to take away my precious life? Thus, it analyzes the idea of just cause and intention in making war.
On the other hand, jus in bello addresses the right conduct in war i.e. the moral conduct during war. In other words, jus ad bellum is distinguished from jus in bello in that the later connotes the justness of the way in which violent means is applied in war (Weeks, 2010) . Thus, these two concepts are linked to another just war principle—jus post bellum which does not just deal with just cause and the right conduct in war but the morality of after-war settlement, reconciliation and rebuilding.
2. Conceptual Clarification of Key Terms
The key concepts that are associated with this work are: just war theory and global peace. The just war theory is a “doctrine” or “military ethics” which provides a moral justification of war and the means adopted in war. In the words of Robert Audi, it is “a set of conditions justifying the resort to war (jus ad bellum) and prescribing how war may be permissibly conducted (jus in bello)” (Audi, 1995) . Thus, it is a Western ideology of ethical evaluation of war which specifies how war is to be carried out in a morally accepted way (Maduabuchi, 2016) .
The history of just war theory is rooted in the works of Cicero and Plato. Hence, the foundation of just war theory is laid by Cicero and Plato in the ancient period. In the medieval period, this philosophy grows out of Christian belief beginning with Augustine, which later obtain both religious, secular and legalist form in the modern period (Audi, 1995) . St. Thomas Aquinas was one of the Christian philosophers that championed and developed the just war theory extensively. Just war theory does not subscribe to act of war or terrorism that destroys life. It emanated in response of self-defense of individuals’ right to life. For instance, the modern challenge of insurgency as act of terrorism in today’s world needs the counterinsurgents in an attempt to bring about peace and determinant end to violence.
In more recent time, Thomas Aquinas’ connection with just war theory is found in the works of some philosophers like Michael J. Butler, Aviva Shiller, Robert J. Kaufman, Joe Egerton, Gregory M. Reichberg, Ezekiel Vergara, and so on.
Another important concept that is associated with this work is global peace. In a common man understanding, global peace simply means the world peace. There are many definitions of world peace. According to Femi A. Balogun, world peace is the model state of “non-violence world which provides a basis for peoples and nations to willingly cooperate, either voluntarily or by virtue of a system of governance that protect human’s warfare” (Balogun, 2017) . In line with this view point, Johan Galtung characterizes world peace into two: negative and positive. Negative world peace is devoid of violence or war. But, positive world peace connotes socio-political and economic equality or justice. Hence, it has to do with good “structural integration” or condition that will make people, nations or organizations to attain peace by peaceful means (Grewal, 2022) other than violence. This work is geared to analyse the implications of St. Thomas Aquinas’ just war on global peace. One the basic aims of United Nations Charter is to maintain “international peace and security” (“United Nations Charter”, 2022) .
3. St. Thomas Aquinas Theory of War
The notion of warfare is endemic is Saint Thomas Aquinas’ moral philosophy. Saint Thomas Aquinas starts this inquiry by asking whether war is justifiable in any situation. He made it clear that war is evil itself. Hence, he condemned it by saying that “war is threatened by Our Lord with punishment according to Matt26:52 ‘all that take the sword shall perish with the sword’. Therefore all war is unlawful” (Aquinas, 2020) . Aquinas toes the line of pacifist who sees war as something evil and ought to be eradicated. He goes further to conceive that war is a sin and against Divine command. He buttresses this point with some Scriptural passages (Matt5: 39) “But I say to you, That ye resist not evil: but whatsoever shall smite thee on thy right cheek, turn to him the other also” (The Holy Bible, 2008: p. 887) and (Rom 12: 19) “Dearly beloved, avenge not yourself, dearly beloved, but rather give place unto wrath: for it is written, vengeance is mine; I will repay, said the Lord” (The Holy Bible, 2008: p. 1054) .
Contrary to the tradition of pacifist that condemned war in its entirety, Saint Thomas Aquinas does not forbid war exclusively. He uses Augustine’s sermon on the son of centurion to buttress that war is not totally bad in itself as thus: “If the Christian Religion forbade war altogether, those who sought salutary advice in the Gospel would rather have been counselled to cast aside their arms, and to give up soldiering altogether” (Aquinas, 2020: p. 1813) . On the other hand, Saint Thomas Aquinas uses the counsel of John The Baptist in gospel of Luk3: 14 “And the soldiers likewise demanded of him, saying, And what shall we do? And he said unto them, do violence to no man, neither accuse any falsely; and be content with your wages” (The Holy Bible, 2008: p. 945) to show that military service is not forbidden generally.
Hence, he comes up with the idea of just war. He toes the line of thought of his master Saint Augustine who was the first scholastic philosopher to present a theory on the issue of justice and war. The classical just war theory which provides the basis for customary international law and formal laws of armed conflict (Patterson, 2021) has its origin in Christian theology.1
3.1. Saint Thomas Aquinas’ Concept of Just War
Just war theory is the “notion that resort to armed forces in war is justified under certain condition” (Johnson, 2020) . Although many philosophers have deliberated so much on the issue of just war theory, it was Saint Augustine (354-430) who laid the foundation of just war theory in the middle ages. Saint Thomas Aquinas (1225-1274) “codified Augustine’s reflection into distinct criteria that remain the basis of just war theory as it is used today” (Dorbolo, 2021) . In the Summa Theologica, Saint Thomas Aquinas lays the three essential conditions or criteria that are necessary in order for a war to be just as thus: authority of the sovereign, a just cause and right intention (Aquinas, 2020, pp. 1813-1814) . Thus, these essential criteria for just war will be discussed under the different subheadings below.
3.1.1. Authority of the Sovereign
Saint Thomas Aquinas conceives that a just war is waged by the legitimate authority of the sovereign. Individuals or groups have no right to wage war. Hence, he expresses this idea as thus:
For it is not the business of a private individual to declare war, because he can seek for redress of his rights from the tribunal of his superior. Moreover, it is not the business of a private individual to summon together the people, which has to be done in wartime. And as the care of the common weal is committed to those who are in authority, it is their business to watch over the common weal of the city, kingdom or province subject to them. And just as it is lawful for them to have recourse to the sword in defending that common weal against internal disturbances, when they punish evil-doers (Aquinas, 2020: p. 1814) …
In addition to this, Saint Thomas Aquinas uses certain Scriptural passages to support the use of sword to defend the people against the external enemies: “(Rom13:4): For he is the minister of God to thee for good. But if thou do that which is evil, be afraid; for he beareth not the sword in vain: for he is the minister of God, a avenger to execute wrath upon him that doeth evil” (The Holy Bible, 2008: p. 1054) and “(Ps82:40): Deliver the poor and needy: rid them out of the land of the wicked” (The Holy Bible, 2008: p. 582) . In line with this assertion, he cites Saint Augustine’s work (Contra Faust. xxii, 75): “The natural order conducive to peace among mortals’ demands that the power to declare and counsel war should be in the hands of those who hold the supreme authority (Aquinas, 2020: p. 1814) .”
3.1.2. Just Cause
Saint Thomas Aquinas expresses that a just war must have a just cause. A just cause may be “a response to a wrong suffered”2 or to correct an inflicted injury. Also, it can be in self-defense of one’s life or territory. In the words of Saint Thomas Aquinas, “a just cause is required, namely that those who are attacked, should be attacked because they deserve it on account of some fault” (Aquinas, 2020: p. 1814) . He cites Saint Augustine’s idea (QQ. in Hept., qu. x, super Jos.): “A just war is to be described as one that avenges wrongs, when a nation or state has to be punished, for refusing to make amends for the wrongs inflicted by its subjects, or to restore what it has seized unjustly” (Aquinas, 2020: p. 1814) .
3.1.3. Right Intention
Saint Augustine believes that a just war must have right intention. He states this idea thus: “it is necessary that the belligerents should have a rightful intention, so that they intend the advancement of good, or the avoidance of evil” (Aquinas, 2020: p. 1814) . The just war tradition conceives that the main motive of going to war is to make peace. On the other hand, other purpose of resorting to war apart from making peace is evil. Saint Thomas Aquinas therefore condemns war for lust of power and extension of territory and other personal aggrandizements as evil. In his own view, war is waged to punish these evils or injustice in order to secure peace.
3.2. Bishops and Clerics as Noncombatant in War
The principle of discrimination is an important principle in Saint Thomas Aquinas just war theory. Saint Thomas Aquinas conceives that human laws give soldiers the duty to warlike pursuits (Aquinas, 2020: pp. 1815-1816) . So, it is his view that bishops and clerics are not meant to fight in war. He gives two reasons for his position as thus:
The first reason is a general one, because, to wit, warlike pursuits are full of unrest, so that they hinder the mind very much from the contemplation of Divine things, the praise of God, and prayers for the people, which belong to the duties of a cleric. Wherefore just as commercial enterprises are forbidden to clerics, because they unsettle the mind too much, so too are warlike pursuits …The second reason is a special one, because, to wit, all the clerical Orders are directed to the ministry of the altar, on which the Passion of Christ is represented sacramentally (Aquinas, 2020: p. 1816) .
Hence, he buttresses that it is improper for bishops and clerics to slay or shed blood. In his own view, it is unlawful for them to fight because war is geared towards shedding of blood.
On the other hand, he considers that prelates and clerics can take part indirectly in war through the authority of their superiors not by taking up of arms, “but by affording spiritual help to those who fight justly, by exhorting and absolving them, and by other like spiritual helps” (Aquinas, 2020: p. 1816) . They can as well order or advise other people to wage a just war.
3.3. Observance of Holy Days in Time of War
Contrary to general Christian opinion that it is unlawful to fight on holy days, Saint Thomas Aquinas believes it is not unlawful to fight on holy days. In his own words, “The observance of holy days is no hindrance to those things which are ordained to man’s safety, even that of his body.” He states categorically that it is lawful to fight on holy days in order to safeguard the common weal of the faithful (Aquinas, 2020: p. 1817) . The common weal is saving innocent people from being slain and preventing other uncountable evils both at the religious and secular level on the Sabbath day.
4. International Applicability of Just War Principles
St. Thomas Aquinas’ just war theory and other just war theorists has provided the ethical basis for war or armed conflict in the international law (Lazar, 2017) . The moral justification of war is categorized into three principles: jus ad bellum-the permissible resort to war, jus in bello-right conduct in war and jus post bellum-morality of after war settlement, reconciliation and rebuilding. St. Thomas Aquinas’ just war theory emphasizes mainly on the principles of -jus ad bellum and -just in bello. The other principle -jus post bellum can be inferred from his theory.
The first criterion of St. Thomas Aquinas’ just war theory buttresses that war can be permissible if it has a just cause-jus ad bellum. Just cause can be self defense or humanitarian intervention to prevent crime (Lazar, 2017: p. 41) . In addition, Matthew B. Helmes conceives that just war can be applicable to targeted killings in order to avert terrorism. Terrorism is a serious danger that threatens internal security and world peace. Averting terrorism is in line with -jus ad bellum but the crucial issue to be considered in this venture is the correct time to execute the act. On this note, Robert J. Kaufman supports the notion of Winston Churchill that using force sooner sometimes can save some unfavorable situations like bloodshed, terrorism, and other inconveniences. This idea seems to be laudable to avert the danger of unjust aggressor like Fulani herdsmen in Nigeria. George Bush for instance waged war with Iraq in 2005 to dispose them of nuclear weapon which posits threat to future catastrophe. In the same line of thought, Israel silent strike on a Syrian nuclear reactor at Al-Kibar in September 2007 is a perfect reflection of this ideology (Holmes, 2011) .
Again, St. Thomas Aquinas’ just war theory is connected with his two other essential criteria of just war such as: authority of the sovereign and right intention. Erick Patterson establishes this connection between them well by conceiving that just cause is embedded on the authority of sovereign “who is acting on a just cause with right intent” (Patterson, 2007) . According to Mark Evans, “a war cannot be considered just unless it has been declared by a leader or leading body formally placed into power by the population it governs and internationally recognized as possessing the inherent authority to do so” (Evans, 2005) .
The third criterion of St. Thomas Aquinas’ just war theory is right intention. St. Thomas Aquinas establishes that just war is intended or aimed at lasting peace. This theory of lasting peace has a strong connection with the second primary tenet of just war theory -jus in bello (the principle of right conduct in war). This is so because jus in bello is geared to lessen brutality, bloodshed and destruction by looking at the future end of war. Thus, this principle will be discussed in details below under ethics of war and rebellion.
4.1. Ethics of War and Rebellion
The second important theory for a just war is jus in bello. It is a theory that deals with the right conduct in war. In other words, it specifies the ethics of war and rebellion. A just war is to be conducted in a morally acceptable way. According to the Code of Conduct for Combatants of International Committee of the Red Cross (ICRC), combat rules are delineated as thus: “1. Fight only combatants. 2. Attack only military target. 3. Spare civilian persons and objects. 4. Limit destruction to what your mission requires.”3 Hence, the International Committee of the Red Cross is a humanitarian organization founded by Henry Dunant and Gustave Moynier in 1863 in Geneva, Switzerland that has a sole power “under international humanitarian law to protect the life and dignity of the victims of international and internal armed conflict.” In 1919, International Federation of Red Cross and Red Crescent Societies was established to provide relief assistance missions responding to large-scale emergencies, including medical services (Wikipedia Contributors, 2021a) . Soldiers or combatants respect their signs (+) (C) on any vehicle of transportation like airplane, ship, ambulance etc during warfare. These combat rules are in line with the principles codified in the international law on the conduct of war.
Hence, the traditionalist just in bello conceives in Stanford Encyclopedia of Philosophy that just war must satisfy three basic principles: discrimination, proportionality and necessity (Lazar, 2020) . The principle of discrimination forbids the killing of civilians or noncombatants. In other words, it discriminates between combatants and noncombatants. War is directed between the armed forces of the nations or parties in conflict.
On the other hand, proportionality is the second principle of just war which ascertains that the means used in war is proportional to the ends of just war. Hence, it prohibits the use of nuclear weapons. The atomic bomb dropped on Japan during the World War II destroyed the city of Hiroshima and Nagasaki (Maduabuchi, 2016) . Nuclear weapon of mass destruction is prohibited in waging war by United Nations because it is capable of ending life on earth.
Proportionality is related to the principle of discrimination in the sense that both of them militate against the intentional killing of noncombatants or innocent civilians. But, killing or harming civilians may be permitted but unintended if only the harms are parallel to the targets the attack is meant to achieve.4
Necessity is another principle of just war in this work which places an obligation on the combatants to choose the least harmful means or alternative possible in the pursuit of military goals. This is what St. Augustine meant when he was admonishing soldiers not to be too brutal. His doctrine of military necessity specifies that “armies can justly take such violent actions as may be necessary to accomplish their assigned task...” But, noncombatants or civilians may be killed unintentionally within the course of this venture.
4.2. International Humanitarian Laws of War
Jus in bello constitutes the law that governs the conduct of war which is known as the laws of armed conflict or international humanitarian law. It is a branch of international law “which seeks to limit the effects of armed conflict by protecting persons who are not participating in hostilities, and by restricting and regulating the means and methods of warfare available to combatants” (Wikipedia Contributors, 2021b) . This law is obtained from international treaties such as case law, general principles of nations, customary international law, etc. These international treaties are codified in Hague Conventions and Geneva Conventions which applies to both international and civil wars. Thus, Jus ad bellum and jus in bello are the components of international law of war. Any breach or infringement of international humanitarian law is regarded as war crime which is punishable by law in the international court of justice.
4.2.1. Geneva Conventions
Geneva Convention is embedded on the principles of just war theory advocated by St. Thomas Aquinas and other just war theorists. The rules that are to be observed in the time of war are contained in the four Geneva Convention of 1949 and their additional Protocols of 1977.5 These treaties express thus:
Persons not directly taking part in hostilities and those put out of action through sickness, injury, captivity, or any other cause must be respected and protected against the effects of war; those who suffer must be aided and cared for without discrimination. Special protection should be given to medical personnel, hospital and medical transports as well as Red Cross personnel, equipment and building (International Committee of the Red Cross, 2023) .6
These treaties are grounded in the respect and dignity of persons. Hence, the Geneva Conventions “are rules that apply only in times of armed conflict and seek to protect people who are not or are no longer taking part in hostilities; these include the sick and wounded of armed forces on the field, wounded, sick, and shipwrecked members of armed forces at sea, prisoners of war and civilians” (Wikipedia Contributors, 2021c) . They are made up of four treaties and their additional Protocols which create “international legal standards for humanitarian treatment in war” (Wikipedia Contributors, 2021c) . According to Wikipedia, The Free Encyclopedia, international legal standards refer to the law of nations which “establishes normative guidelines and a common conceptual framework for states across a broad range of domains, including war, diplomacy, trade, and human rights” (Wikipedia Contributors, 2021d) .
The first Geneva Convention was held on 22 Aug. 1864 which talks about ameliorating the condition of wounded soldiers in the battle. For instance, article 12 stipulates that the wounded and sick soldiers should be treated with compassion without being killed, injured, tortured or subjected to human experimentation (Wikipedia Contributors, 2021e) . Humanitarian organizations provide and care for the wounded and sick soldiers medically and other wise
The Second Geneva Convention deals with improving and taking care of the sick and shipwrecked members of armed forces in the sea which was adopted in 1949. The articles in this convention make provision for neutral vessel or hospital ship to take and treat the wounded, sick and shipwrecked without attack and to protect the religious and medical personnel helping on a combat ship (Wikipedia Contributors, 2021f) . Even though hospital ships cannot be attacked or captured, the wounded, sick and shipwrecked can be taken as prisoner of war.
The Third Geneva Convention has to do with the treatment of prisoners of war which approved in 1929 and revised in 1949. Prisoners of war are members of opposing armed forces who are captured by the other party in conflict. The articles in this convention recommend that prisoners of war must be protected and treated kindly; medically and other wise without discrimination from the period of their capture till their repatriation (Wikipedia Contributors, 2021g) . Also, the medical personnel of the enemy and chaplain of the enemy are to be treated with care and respect.
Finally, the Fourth Geneva Convention deals with humanitarian protection and defense of civilians in time of war or war zone which was assigned into bill in 1950. The articles of this convention make provision for protection of noncombatants including members of armed forces who have surrendered their arms and combatants who are “out of the fight” as a result of wound, detention or any other reason be treated well without murder, torture, mutilation or capital punishment (Wikipedia Contributors, 2021h) . It also prohibits all manners of intimidation, terrorism, pillage, reprisals against protected persons and their properties (Wikipedia Contributors, 2021h) . Likewise, the occupying power has the responsibility of providing education for children as well as maintaining the medical, public health and hygiene in the occupied territory.
Serious breaches or violations of treaty of Geneva Conventions are considered as war crimes. War crimes are legalized and punishable by law. Thus, Geneva Conventions still serve as the main source of the present international humanitarian law.
4.3. Hague Conventions
Geneva Conventions are associated with Hague Conventions. Both of them have to do with warfare. Geneva Conventions deal with how human beings ought to be treated by Governments in war time which is fashioned to care and protect the injured parties or victims of war. Hague Conventions, on the other hand, establishes the rules for conducting war (Fruchterman, 1983) .
Hague Conventions 1899 and 1907 set up the laws and principles that belligerents must abide during warfare by defining the methods and means of war. Method implies the “tactics or strategy used in hostilities against an enemy in time of conflict” whereas means deal with weapons of warfare (Bouchet-Saulnier, 2021) . Different international humanitarian law like the 1899 and 1907 Hague Conventions and Geneva Conventions set out the standards that restricts or prohibits the use of violence which limits the method of warfare in the international and civil (non-international) armed conflict. Articles of the rule of Hague Conventions forbid amidst others the use of means and methods of warfare that are very detrimental to human being such as perfidy, terror, famine or starvation of civilians, reprisals against nonmilitary objectives, indiscriminate attacks against protected persons and civilians and so on (Bouchet-Saulnier, 2021) .
On the other hand, the declarations of Hague Convention on July 29, 1899 focused on matters dealing with peaceful settlement of international disputes. In addition to this first convention, there are laws and customs of war that were reinforced in the second Convention of 1907 like “the prohibition on the use of projectiles that disperses asphyxiating gas and the prohibition on the use of bullets that expand or flatten easily in the human body”.7 Also, certain issues were addressed in The Hague Conventions of October 18, 1907 such as: “the pacific settlement of disputes (based on The Hague Convention I of 1899); the opening of hostilities (The Hague Convention III; the laws and customs of war (Convention IV, with annexes and regulations, which develops Convention II of 1899 and cases of military occupation); the rights and duties of neutral powers in case of war on land (V); the status of merchant ships at the outbreak of hostilities (VI); the conversion of merchant ships into war ships (VII); the laying of automatic submarines contact mines (VIII); the bombardment by naval forces in time of war (IX); the adaptation to maritime war of the principles of the Geneva Convention of 1906 (X); restrictions with regard to the exercise of the right of capture in naval war (XI); the establishment of an international prize court (XII) and the rights and duties of neutral powers in naval war (XIII)”.8
4.4. International Committee of Red Cross
International Committee of Red Cross (ICRC) is the humanitarian agency that functions as the guardian or custodian of Geneva Conventions for the enforcement of international humanitarian law pertinent in armed conflict and to take official notice of any complaints dealing with alleged violations of international humanitarian law of armed conflict (Sandoz, 2021) . This organization plays a special role to comprehend and spread the knowledge of international humanitarian law of war or armed conflict as well guard the law in order to protect it from those who may work against it.
Hence, International Committee of Red Cross (ICRC) is “an impartial, neutral and independent organization whose exclusively humanitarian mission is to protect the lives and dignity of victims of war and internal violence and to provide them with assistance”. It has a legal authority under international law to visit and care for prisoners, arrange relief actions, bring back together parted families, and provide other humanitarian services in time of war or armed conflict (International Committee of Red Cross (ICRC), 2021) .
Moreover, it also cares for the wellbeing of the environment by creating general awareness of the hazards of excavating the explosive or bomb leftovers of war (International Committee of Red Cross (ICRC), 2021) . Its headquarter is located at Geneva in Switzerland.
4.5. War Crimes
International Committee of Red Cross (ICRC) is the humanitarian agency that enforces the international humanitarian law. It is their duty to report the infringements of this law to the international community. According to the Customary IHL Database of ICRC, rule 156 defines war crimes as serious violations of international humanitarian law.9
The notion of war crimes is a new invention. It emanates in 19th and 20th century when international humanitarian law (law of armed conflict) was enacted. The Hague and Geneva decree make out many breaches of its rule (United Nation, 2021) . Examples of war crimes include: genocide or ethnic cleansing, waging war of aggression, rape or any other form of sexual violence, unlawful and random destruction of civilian property, pillage and so on. Many serious violations of laws of international armed conflicts enshrined in the international law amidst others like: intentional attack against humanitarian service personnels, hospital etc., using poisonous or diabolical weapons, starvation of civilians, enlisting under age children into armed forces and so on (United Nation, 2021) . In summary, the war crimes in the international humanitarian law can be classified into:
a) war crimes against persons requiring particular protection; b) war crimes against those providing humanitarian assistance and peacekeeping operations; c) war crimes against property and other rights; d) prohibited methods of warfare; and e) prohibited means of warfare (United Nation, 2021) .
War crime trials are conducted in the international court of justice, international criminal tribunal or national court. The prosecution of war criminals ranges from death sentence, long term or life imprisonment, sentence to lesser terms depending on the gravity of the offence.
Although the international law of armed conflict seems to replace just war theory as the ethical law governing the conduct of war in the modern period, the law of armed conflict or international humanitarian law including the Geneva and Hague conventions originated from the principles of St. Thomas Aquinas and other just war theorists.
5. St. Thomas Aquinas’ Just War Theory and Global Peace
St. Thomas Aquinas’ just war theory is geared towards making peace. Carsten Stahn conceives that peace is not a natural or normal state rather it is something that needs to be constructed (Stahn, 2021) . A just peace has many connotations. In a sense, a just peace is connected with the nature of warfare i.e. a peace created by consent which vindicates rights and prevents future violence. It is the peace that is embedded on the principle of justice. Injustice is the subject matter of many conflicts or war. One of the basic criteria of St. Thomas Aquinas’ just war theory is the principle of just cause. A just cause can be violation of rights of citizens or self-dense of one’s life or territorial integrity.
In a broader sense, peace does not only imply absence of violence. According to the UN Declaration on the Right to Peace, “peace is not only the absence of conflict but also requires a positive, dynamic participatory process where dialogue is encouraged and conflicts are solved in a spirit of mutual understanding and cooperation, and socio-economic development is ensured”.
5.1. Morality of after War-Settlement
The ethical justification of war enshrined in jus ad bellum—the permissible resort to war and jus in bello—right conduct in war is meant to promote peace. Hence, the ethical principles that are inherent in jus in bello consider the future end of war. It has to do with right ending of war. The right ending of war is geared towards just peace. However, the ethical justification of just war theory does not only deal with jus ad bellum and jus in bello. It also embraces the morality of after-war settlement, reconciliation and rebuilding—jus post bellum.
St. Thomas Aquinas’ just war theory is inferred in jus post bellum which is the third criteria of the just war theory. His idea of tranquillitas ordinis is a Latin axiom which means “tranquility of order”. This is a term which has to do with the Roman Catholic tradition of just war theory that confers meaning in theology and politics. It is the notion of “divine order imposed on the universe” which serves as the foundation of Catholic teaching on peace. George Weigel envisages that tranquillitas ordinis offered a footing for the establishment of just peace in line with just war theory (Wikipedia Contributors, 2021i) .
Jus post bellum is the final principle of the just war theory. It addresses the issue of justice after war which has to do with peace agreements or treaties, war crime trials and war reparation, rebuilding, reconciliation etc. (Wikipedia Contributors, 2021j) . This theory is more than just the third principle of the just war theory because just post bellum is very important to repair the damaged relationships before and during the time of war (Stahn, 2021: p. 18) .
5.1.1. Settling War Crimes and Injustice
The third criteria of St. Thomas Aquinas’ just war theory stipulate that “that war may be waged with right intention for a rightly ordered peace”. Hence, his just war theory serves to attain just peace which demands that the “root cause of aggression” has been eliminated. This is in line with principle of jus post bellum which deals with the issue of justice after war. It places a great obligation on the victors to ensure that the vanquished are well governed and resuscitated economically and otherwise in order to avoid sowing the seeds of discord that may give rise to future war (Bellamy, 2008) .
Since combatants ought to be held responsible to give account on how war ended and peace managed, jus post bellum demands that the war criminals be tried in the international criminal court (ICC) or tribunal. Individuals including sovereigns who violated the international laws of war are punished in order to restore the social harm created by conflict which serves as a deterrent for crime and war prevention. Hence, war crimes ranging from genocide; grave bleaches of Geneva and Hague Convention; crimes against humanity like violence against civilians as in the case of murder, rape, imprisonment, slavery or torture; crimes of aggression like encroachment into other States’ territorial boundaries and so on are punishable under national and international law (Klobucista, 2022) . The punishment ought to be both retribution and rehabilitation. This implies that the punishment is not just to kill them but also to reform or rehabilitate them.
However, failure to address the war crimes on those who are grievously wronged by aggressions like genocide and other violence against civilians or humanity will lead to the execution of further injustice on the innocents and victims of war (Bellamy, 2008) . For instance, the Igbo are still suffering the effect of Nigeria/Biafran civil war of 1967-1970 till date because the candid world has failed to try the war criminals in the Nigeria civil war. This injustice is still sowing the current seed of discord and aggression in the South Eastern Nigeria.
In line with this viewpoint, war crime trial and punishment of war criminals is not enough to address the issue of just peace after war, the parties formerly in conflict owe each other the duty to compensate or restitute war related wrongs in order to prevent harm after war (Koszela, 2021) . In other words, infringing or violating the just war principles calls for compensation on those who are wronged or the victims. The compensation theory of just post bellum makes provision for “the benefit of imposing additional restraints on the use of overwhelming force” which serve to incur an increase on one’s post war compensation (Koszela, 2021) . Hence, Adam Koszela expresses thus:
…since on the compensation theory of jus post bellum post-war compensation is owed for much more than is usually thought, war becomes a (morally) very expensive business. This is a benefit of the theory, I think. While wars are sometimes justified, even required, they do involve massive amounts of human suffering. If the realization that going to war will typically generate substantial debts of compensation restrains agents and states from going to war, this will generally be for the better (Koszela, 2021) .
Thus, this Adam Koszela’s compensation theory of just post bellum is good which may serve to prevent future wars. This is so because agents and states may be discouraged from waging war after considering the substantial debts of compensation that jus post bellum principles entail on the war victims. .
5.1.2. Reconciliation and Rebuilding
Jus post bellum reconstruction has to do with reconciliation, rebuilding, restitution, reparation, amidst others. Peace building and reconciliation are important to create a long-lasting peace that will prevent future conflicts, hostilities or wars (Hilpold, 2015) . This is quite different from peacemaking or peace keeping which can only serve to stop the ongoing war which addresses only the external dimension of conflict. But, peace building is an after war effort to tackle the internal conflict that might give rise to another war. It also incorporates the responsibility to rebuild what are destroyed during the wartime. Rebuilding and reconstruction after war do not have to do with only material edifice, legal infrastructure which serves as the fabric of the society is inclusive. Moreover, promoting good governance and sustainable development for vanquished is necessary to build a lasting peace.
Peace building can go beyond the just war theory. In this regard, peace is conceived as a shared responsibility which involves not only the just war theorists but also international organizations or third parties (Stahn, 2021: p. 8) . Just peace is not only limited to civil or internal war or conflict. It is also associated with international or global peace which intends to resolve severe injustice among peoples and nations to prevent its future occurrence and to achieve peaceful reconciliation or peacemaking. Thus, individuals, civil societies, government, churches, humanitarian agencies, and international community have the moral obligation to work together towards promoting global peace in this 21st century in order to make the world a better place.
5.2. Path to Global Peace: All Other Means of Conflict Resolution
World peace is a noble ideal which demands for building and rebuilding of the global world on the principles of justice and peace by ending violence. St. Thomas Aquinas’ just war theory aims at right ending of war which is geared towards peace. If the injustice that gives rise to war is not resolved after war, it can give rise to future war. On this note, Paul Gilbert envisages that beginning of new wars raises three fundamental issues such as: how to end wars, how to resolve the conflicts that give rise to war and how to produce the conditions in which they are unlikely to occur (Gilbert, 2003: p. 134) . The just war theory espoused by St. Thomas Aquinas and other just war theorists deals with the first criteria i.e. how to end wars.
On the other hand, just post bellum principles address the two other important issues: how to resolve the conflicts that give rise to war and how to produce the conditions in which they are unlikely to occur which are crucial for global peace. Hence, it is geared to eliminate “any possible evil actions caused by social injustice, anger, strive for power and or religious intolerance” (Švaňa, 2020) . The need to end violence and establish justice and peace is a global call in this 21st century. On this ground, Ben Okwu Eboh conceives that there are two different approaches of resolving conflict for peace to reign in the society. The two ideological approaches according to him are: permanent conflict view and healthy realism view (Eboh, 2005: p. 116) .
Permanent conflict view is the ideology that the relationship between people and nations is characterized by conflict, competition and antagonism. This view point believes that might is right. In this regard, justice is the interest of the stronger. Peace is built on the fear of other great nations. He criticizes such peace as unjust and not befitting of ideal human society because it cannot resolve the tensions among people and nations in this modern age.
On the other hand, healthy realism is the opposite of former which conceives that peace and justice can be built on a stable and universal foundation (Eboh, 2005: p. 117) . Hence, this ideology for him envisages that people, communities and nations need a change of heart or attitude in order to make amend for the injustice perpetrated against others. It calls for reconciliation, justice and peace among peoples and nations. Thus, it recommends that political, economic, social and cultural relation and system must be based on the principle of solidarity and dialogue which is to be monitored by the world community to take care of the common good of all nations (Eboh, 2005: pp. 118-119) . This is the kind of peace that is to be reached by agreement and persuasion.
Dialogue is the ideal means of conflict resolution. Cicero rightly observes that discussion or dialogue is characteristic of man in the case of a state in its external relation but physical force of the brute animal. Nevertheless, man can resort to force only when discussion or dialogue fails. This is in line with St. Thomas Aquinas’ just war theory. The principle of just cause in his just war theory is based on the authority of the sovereign “who is acting on a just cause with right intent”.
6. Evaluation
St. Thomas Aquinas has contributed so much to the philosophy of war or armed conflict (military ethics) in the medieval period which is still relevant in this contemporary world. However, there are certain loopholes in his philosophy. In the first instance, his just war theory is not original to him. Thomas Aquinas just takes up Augustinian just war theory and modified it by just adding right intent in order to differentiate it from Augustinian theory.
However, Aquinas just war theory emphasizes the three essential conditions or criteria of just war which fall mainly on the principle of jus ad bellum. Even though the other two important principles of just war theory such as jus in bello and just post bellum can be inferred from Thomas Aquinas’ just war theory, the jus ad bellum principle cannot serve as the only essential principle of just war tradition. Thus, the three important principles of jus ad bellum, jus in bello and just post bellum are very essential in the just war tradition in such a way that one cannot do in isolation from the others.
Although the international law of war or armed conflict originates from the principles of St. Thomas Aquinas and other just war theorists, the just war tradition seems to be replaced by the international humanitarian law of war which is codified in the Geneva and Hague conventions as the ethical law governing the conduct of war in the modern period. But, a critical look at the comparative analysis of both just war theory and international law of war depicts that the international law of war is more extensive than the just war tradition because it deals with humanitarian treatment in the time of war as well as the rules of warfare which define both the methods and means of war. In addition, the international law of war provides the legal backing for the enforcement of this law among the member states of United Nations.
Again, just post bellum is very crucial principle of just war theory that addresses the issue of justice after war which is a conditio sine qua non “to repair the damaged relationships before and during the time of war”. On the other hand, Thomas Aquinas’ just war tradition seems to neglect the presuppositions of the principle of just post bellum (Gilbert, 2003: p. 20) . Hence, peace building, reconstruction and reconciliation after war amidst others are the principles of just post bellum which are indispensable for global peace.
The prospects of just war theory are enormous but that will not undermine the fact that war is evil. In the words of Ezekiel Vergara, “war is pandemic… the current experience of Covid-19 pandemic is similar to that of warfare situation”. This is very inimical to human well being. War is a plague. The heinous or devastating effects of war on human lives, culture and civilization are such that war may not be morally permissible. According to Michael M. Uhlmann, “the idea of just war is simply convenient sophistry that arbitrarily exonerates certain kinds of violence” (Uhlmann, 2021) . Thus, one can say that the just war theory notwithstanding its presumptions in a way is synonymous with the philosophy of might is right.
Thomas Aquinas just war theory is based on the three essential conditions of just cause, legitimate authority and right intention as indispensable for just war. But, Bertrand Lemennicier expresses that it is not always easy to discern or determine these basic criteria of Thomas Aquinas’ just war theory. In the first instance, he believes that it is difficult for the sovereign to define the notion of just cause as the permissible resort to war because there is always this tendency for all the combatants to lay claim to just cause as the justification their action (Lemennicier, 2003: p. 4) . In addition to this, he envisages that Thomas Aquinas’ idea of legitimate authority that declares when it is just to fight is ambiguous. In his own view, it is somehow improper for the legitimate authority who determines what is just and unjust to be the one to declare the war. Again, he conceives that it is difficult to detect the good or rightful intention that is not marred by private interest (Lemennicier, 2003: p. 5) . Thomas Aquinas concept of right intention implies that war is waged when all peaceful alternatives have been exhausted and war is embarked as a last resort. But, Bertrand Lemennicier criticizes this view by saying that using war as a last resort implies diplomacy and diplomacy cannot do without case bargaining and bad compromises. This is so because one cannot bargain or make concession with evil government.
However, the last criterion of just war for him is that there must be reasonable chances of success. This view point contradicts the goal of just war which is self-defense. On this note, one can say that this last criterion of just war is self contradictory which implies that the ends justify the means. This endorses the permanent conflict view approach to resolving conflict which supposes that might is right. This study stands to criticize this ideology. What it means is that peace is built on the dread of other powerful nations. This type of peace is contrary to the third principles of just war tradition—just post bellum which amounts to cold war that will give rise to future war.
Thomas Aquinas’ just war theory seems to apply mainly to international war. It does not account for civil or internal conflict or war which appears to denounce individual rights. In a free state, individuals have the right to protect or preserve their life and properties. In this case, they have the power to protest against their corrupt government. The authority of their government can be questioned in such a way that people can chose to die in order to preserve their life, freedom and property (Lemennicier, 2003: p. 8) . Thomas Aquinas’ theory of just cause can be relevant in individual protection in order to recover their properties that are wrongfully taken by others. Individuals who are victims of injustice have the basic right to revolt against their bad government in such a way as to get their freedom.
Notwithstanding the lacuna in Thomas Aquinas just war theory, one cannot throw away the positive prospects of Thomas Aquinas’ just war theory. Doing that implies throwing the baby away with bath water. Thomas Aquinas’ just war serves a good mediation between the extreme positions of real politik and pacifism. Hence, the three essential conditions of just cause, legitimate authority and right intention that is indispensable for just war in Thomas Aquinas’ just war theory is still relevant. On the other hand, Bertrand Lemennicier’s criticism of these three essential conditions of Thomas Aquinas’ just war seems not to hold enough water.
In the first instance, these three basic conditions are closely connected. All of them revolve around the sovereign who is voted into power as the representative of the people. He is the true custodian of law and morality. The onus lies on the masses to elect a good person who will govern the people in good conscience and morality in order to curb the problem of assumption of just cause as motive of waging war behind their ill or selfish interests. The same thing applies to the criticism he leveled against the third condition of Thomas Aquinas’ jus war that it is not easy to detect the good intention that is not marred by private interest. A good leader is the one who promotes common good or public interest over his private or selfish interest. Again, the criticism which he levels against the second condition of legitimate authority does not hold because he did not specify the correct agency that is responsible for declaring war whether it is international law, or international organization like UN or individuals who are victims of injustice.
7. Conclusion
This study has examined the epistemic implications of Thomas Aquinas’ just war theory on global peace. The three essential conditions Saint Thomas Aquinas’ just war theory are geared to promote just peace. Just peace is a peace that has to do with justice which is connected with the nature of warfare. Thus, Thomas Aquinas’ just war theory has great relevant implications to global peace. The morality of after-war settlement, reconciliation and rebuilding endemic in jus post bellum is relevant for global peace. Today, the whole world is engrossed with antagonism and war. There is the need for people and nations to lay down their arms and embrace peace through dialogue and solidarity in order to end conflict. This calls for the eradication of all the violent acts propelled by anger, exploitation or social injustice, religious bigotry and thirst for power. This work states that war can stand on the authority of sovereign who is acting on just cause for right intent only when all peaceful measures have been exhausted and war is undertaken as a last resort for the purpose of lasting peace. In that case, war has to be based on just war principles and international law of war.
NOTES
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