A Political Philosophy and Educational Essay for Deliberative Democracy
Note: This paper examines the material causes of war and argues that the development of civilization has eliminated them all. The paper grounds this argument in just war theory, sociological analysis of the transition from mechanical to organic solidarity, and historical analysis of how rule of law has emerged to replace warfare in dispute resolution.
For political educators, the paper provides a framework for helping citizens understand why war was once necessary, why it is no longer necessary in most circumstances, and why even when war might be justified, civilized nations should approach it with extreme reluctance as the costs outweigh the benefits. The paper argues that understanding war in this context allows citizens to evaluate arguments for military action critically, distinguishing genuine security concerns from pretexts for war.
For policymakers, the paper suggests that the default position should be a peaceful resolution of disputes through legal and diplomatic means. War should be considered only when genuinely necessary for self-defense, and even then, only after exhausting peaceful alternatives.
For global citizens, the paper offers a perspective on the long trajectory of human development toward integration and away from warfare. It suggests that the future of civilization lies in strengthening international law, promoting economic integration, and building institutions that make peace the rational choice—all possible only under democracy.
In an era when some leaders again invoke calls to national greatness, military power, and dominance, this paper provides a philosophical foundation for arguing that true civilization—and genuine security—lies not in military strength but in the capacity to live peacefully with diverse others under rule of law.
Abstract
The paper analyzes the material and organic causes of war and claims that the development of civilized society has systematically removed these causes. Drawing on just war theory, sociological analysis, and political philosophy, the paper shows that the two foundational material conditions that made war inevitable in tribal and barbarian societies—mechanical solidarity and dependence on natural resources—no longer exist in contemporary civilized nations. Organic solidarity, interdependence based on differentiation or division of labor, has replaced the first condition. Interdependence among autonomous individuals whose survival depends on specialized economic activity rather than territorial conquest has replaced the second. Besides, systems of rule of law have emerged to mediate disputes that in the past required military resolution. The paper concludes that in civilized society, war lacks organic justification except in two limited circumstances: defense from unprovoked aggression and removal of undemocratic governments that prevent citizens from removing them through electoral processes. This framework provides citizens and policymakers with a rationalized basis for understanding when war might be justified and, more importantly, why civilized nations should exhaust all alternatives before resorting to military conflict.
Introduction: Rationalizing War in the Modern Era
War remains a persistent feature of international politics despite dramatic advances in human cooperation, prosperity, and moral understanding. Yet the persistence of war does not show its necessity. Rather, it may reflect the incomplete transformation of political institutions and international systems to match the material conditions of civilized society. This paper argues that in civilized society, there are no organic or material causes that make war inevitable or necessary, except in the limited cases of self-defense.
To reach this conclusion, the paper proceeds in five parts. First, it examines the material causes of war identified in historical, political philosophy, particularly in the work of Hugo Grotius, and explains why these causes operated in tribal and pre-civilized societies. Second, it explains the sociological transformation from mechanical to organic solidarity and its implications for the necessity of warfare. Third, it shows how the division of labor and resulting economic interdependence have eliminated the material scarcity conditions that previously justified war. Fourth, it explains how systems of rule of law have emerged to perform the conflict-resolution function that war once served. Fifth, it concludes with a framework for when war remains justified in civilized society—specifically, self-defense and removal of oppressive governments—and argues that civilized nations should approach all other conflicts through legal and diplomatic means.
This analysis is important for political education because it provides citizens with a rationalized understanding of war that is neither naively pacifist nor uncritically militaristic. It explains why war was once necessary, why it is no longer necessary in most circumstances, and why, even if war might seem justified, civilized society should approach it with extreme reluctance and only after exhausting all alternatives. In an interconnected world, the costs of war outweigh the benefits, and this is sufficient reason for us to show that we are no longer barbarians.
The Material Causes of War: Historical Foundations
Grotius and the Justifiable Causes of War
Hugo Grotius, writing in the early 17th century amid the religious and political turmoil of the Thirty Years’ War, sought to establish a systematic framework for understanding when wars could be just. His work, De Jure Belli ac Pacis (On the Law of War and Peace), became foundational to just war theory and continues to influence contemporary international law (Grotius, 1625/2005).
Grotius argued that “the sources from which wars arise are as many as those from which lawsuits spring; for where judicial settlement fails, war begins” (Grotius, 1625/2005, p. 81). This observation is crucial: Grotius understood war as arising when other mechanisms of dispute resolution—legal systems, negotiation, arbitration—were absent or had failed. Wars, in his view, emerged not from abstract grievances but from concrete material injuries and conflicts over rights and property.
Grotius identified three primary justifiable causes of war (Grotius, 1625/2005):
Self-Defense and Protection of Property: The first justifiable cause was defense against injury—both to self and to property. If someone attacked another person, stole their property, or threatened their safety, the attacked party could resist and, if necessary, wage war to protect themselves and recover what was taken. This cause of war originated in the fundamental human right to preserve oneself and one’s possessions.
Reparation for Injury: The second cause was reparation for wrongs already committed. If one party had wronged another—by theft, violence, or breach of agreement—and refused to make restitution, the wronged party could rightfully wage war to compel reparation. This cause of war reflected the principle that when peaceful legal remedies were unavailable, military force could rightfully enforce justice.
Punishment: The third cause was punishment of wrongdoing. Grotius argued that a sovereign power could wage war against those who had committed serious wrongs—violations of natural law, crimes against the innocent, or breaches of sacred obligations—to punish these wrongs and prevent their repetition (Grotius, 1625/2005).
Importantly, Grotius emphasized that these causes of war were justifiable—meaning they required actual injury or wrong, public authority to declare war, and legitimate purpose. They were not merely pretexts that any party could claim; they required actual evidence of wrong and required that peaceful remedies had been exhausted. As Grotius stated, “No other just cause for undertaking war can there be except injury received” (Grotius, 1625/2005, p. 82).
The Material Basis of War in Tribal and Pre-Civilized Societies
Behind Grotius’s categories of justifiable causes lay material conditions that made war inevitable in tribal and pre-civilized societies. We can understand these conditions through sociological analysis and historical examination.
Scarcity and Competition for Natural Resources: In tribal and early agrarian societies, survival depended directly on access to land, water, games, and other natural resources. The carrying capacity of available land limited populations. When populations grew beyond sustainable levels, the only options were famine, migration, or conquest. Under these conditions, tribal groups competed directly for territory and resources. When one tribe’s population increased or when drought reduced available resources, war became a practical means of securing survival (McNeill, 1982; Keegan, 1993).
Absence of Alternative Dispute Resolution Systems: Tribal societies lacked formal legal systems, courts, or mechanisms for peaceful dispute resolution at the inter-tribal level. When disputes arose—over theft, injury to members, violations of agreements—there was no neutral authority to adjudicate. The wronged party had to seek a remedy through self-help, which often meant warfare. Without law, force became the primary mechanism for enforcing rights and resolving conflicts.
Isolation and Tribal Identity: Isolation characterized tribal societies. Travel was difficult; communication with distant groups was rare. Each tribe had its own identity, often reinforced by language, religion, kinship, and cultural practices. People considered members of their own tribe fully human, worthy of rights and protection. People often considered members of other tribes’ outsiders, potential threats, or not fully human. This psychological distance made war against other tribes psychologically acceptable in ways it would become as societies integrated (Keegan, 1993).
Immediate Threats to Survival: In tribal societies, people often understood war as a response to immediate threats. Other tribes might raid for resources or captives. These raids were not merely military operations; they threatened survival itself. Under conditions of genuine threat, war became a rational response to immediate danger.
The Transformation to Civilized Society: From Mechanical to Organic Solidarity
The transition from tribal to civilized society involved a fundamental transformation in how people were bound together socially and economically. Émile Durkheim, the pioneering sociologist, identified this transformation as the shift from mechanical solidarity to organic solidarity (Durkheim, 1893/1984).
Mechanical Solidarity in Tribal Societies
Mechanical solidarity characterizes societies where individuals are bound together by similarity. People share the same religion, language, values, and way of life. They perform similar roles—hunting, gathering, simple agriculture. Differences among individuals are minimal. A strong collective conscience holds together the society—shared beliefs about right and wrong, sacred and profane, us and them (Durkheim, 1893/1984).
In mechanical solidarity, individuals identify primarily with their tribe. The group’s interests supersede individual interests. The group does not tolerate deviations from collective norms. Violators face severe punishment. Identity is tribal identity; loyalty is to the group.
Under conditions of mechanical solidarity, war becomes the primary means of expressing tribal identity and competing for resources. When one tribe wages war against another, it is not merely an economic competition; it expresses tribal identity and solidarity. The tribe that successfully wages war demonstrates its superiority and dominance, thereby reinforcing internal cohesion.
Besides, in mechanical solidarity, individuals have no economic relationship with members of other tribes. They do not depend on trade with outsiders; they depend on their own tribe’s ability to secure resources. This makes war a direct form of competition: your tribe’s gain is another tribe’s loss.
Organic Solidarity in Civilized Society
Organic solidarity characterizes societies where individuals are bound together not by similarity but by interdependence. People perform different specialized roles—farmers, craftspeople, scholars, traders. They have different values, beliefs, and ways of life. Yet society holds together because individuals depend on each other to perform their specialized functions. Farmers produce food for everyone; craftspeople produce tools and goods; scholars produce knowledge and wisdom. This interdependence creates social cohesion more durable than similarity (Durkheim, 1893/1984).
The transformation into organic solidarity involves several key changes:
Development of Division of Labor: As societies develop, people begin to specialize. Rather than each family producing everything it needs, people specialize in particular economic activities. This specialization increases productivity tremendously. One blacksmith can produce better tools than many families making tools themselves. One farmer using specialized techniques can produce more food than multiple families farming independently. This increased productivity allows larger populations to live in the same territory without competition (Durkheim, 1893/1984).
Emergence of Trade and Exchange: Specialization creates a need for trade. The person who specializes in making pottery needs food, clothing, and tools. The farmer needs pottery and tools but produces surplus grain. Trade allows each to exchange surplus for needed goods. Over time, markets develop; strangers trade with each other across tribal boundaries (McNeill, 1982).
Development of Cities and Integration of Diverse Groups: As trade expands, people from different tribes and backgrounds find themselves living in the same location. A city becomes a place where people from different original tribes, with different languages and cultures, live together in proximity. This requires the development of mechanisms for peaceful coexistence—shared laws, dispute resolution systems, common languages or lingua francas (Keegan, 1993).
Formation of Political Institutions and Rule of Law: To manage increasingly complex societies with diverse populations and specialized roles, political institutions develop. Formal legal systems emerge to define rights and resolve disputes. Government bureaucracies develop to manage public functions. These institutions are not based on tribal identity but on residence in the same territory and membership in the same political community. Importantly, these legal institutions perform the dispute-resolution function that war once performed (McNeill, 1982).
Why Organic Solidarity Eliminates Tribal War
The shift from mechanical to organic solidarity eliminates the material basis for tribal war in several ways:
Integration Replaces Isolation: In mechanical solidarity, tribes were isolated. In organic solidarity, people from different backgrounds are integrated into the same society. They interact daily in markets, workplaces, and public spaces. They have friends and business partners from different backgrounds. Primarily, their interdependence through division of labor and markets replaces dependence on scarce natural resources. This integration makes war against people who are now one’s neighbors and partners psychologically and morally difficult.
Interdependence Replaces Independence: In mechanical solidarity, each tribe was economically independent. In organic solidarity, individuals and regions depend on each other for survival and prosperity. A farmer in Region A depends on the blacksmith in Region B and the scholar in Region C. The blacksmith depends on the farmer and the merchant. Breaking the bonds of trade through war damages everyone, including the potential victor.
Common Governance Replaces Tribal Autonomy: In mechanical solidarity, each tribe had its own governance and laws. In organic solidarity, people from different backgrounds accept common governance and legal systems. Although conflicts might occur, people resolve them through law instead of warfare. Courts resolve a dispute between a farmer from Region A and a merchant from Region C, not by war between regions.
Shared Citizenship Replaces Tribal Identity: In mechanical solidarity, people identified with their tribe. In organic solidarity, people identify with their political community or nation. A person is a citizen of a nation rather than a member of a tribe. This citizenship involves both rights and obligations, but it no longer depends on tribal lineage or origin. People from different original tribes can become citizens of the same nation and community.
The Economic Transformation: From Scarcity to Interdependence
The development of organic solidarity coincides with a fundamental transformation in economic conditions. Systems of interdependence based on specialized production and trade have replaced the scarcity that drove war in tribal societies.
The Division of Labor and Productivity
Adam Smith, writing in the late 18th century, famously demonstrated that specialization and division of labor dramatically increase productive capacity (Smith, 1776/1976). His example of the pin factory showed that through division of labor, productivity could increase hundreds of times. Rather than each worker making complete pins, workers specialized in particular tasks—drawing wire, cutting it to length, sharpening points, attaching heads. This specialization allowed a few workers to produce far more pins than if each worker made complete pins independently.
This principle extends to all economic activity. A farmer using modern agricultural techniques (themselves products of accumulated specialization and knowledge) can produce enough food to feed not only themselves but many others. Tool manufacturers can produce more valuable tools more efficiently than general craftspeople. A person specializing in transportation can move goods more efficiently than if each producer transported their own goods.
The result is that modern economies produce vastly more than tribal economies. Where a tribe might struggle to feed itself, a modern economy can feed large populations with a significant surplus. Competition for scarce resources no longer causes war. There is no longer a genuine scarcity of basic necessities in modern economies. We can produce food, shelter, and basic goods in abundance. The problem is not production but distribution (Sen, 1999).
Economic Interdependence and Mutual Vulnerability
The development of specialized production creates economic interdependence. No one person can produce everything they need. Instead, each person depends on many others:
- For tools, the farmer relies on the blacksmith; for equipment, the mechanic; for market access, the merchant
- The merchant depends on the farmer for goods to trade, the transporter for moving goods, and the accountant for managing finances
- The manufacturer depends on the raw material producer, the worker, the engineer, the merchant
- The scholar depends on the librarian, the publisher, the institution, and the readers who find value in their work
This interdependence means that each person benefits from peaceful cooperation with many others. Conversely, disruption of these cooperative relationships harms each person. War disrupts trade, damages infrastructure, diverts resources from productive to destructive purposes, and destroys the foundation of mutual prosperity.
Consider the case of a nation that wages war against a trading partner. Even if the nation wins militarily, it faces enormous costs:
- The shift of resources to military production disrupts manufacturing and agriculture.
- Trade ceases, depriving the nation of goods it specialized in trading for.
- Destruction of infrastructure damages productive capacity.
- Warfare consumes resources that could have generated prosperity.
- Even if the nation gains territory, it acquires damaged land and infrastructure, not functioning productive capacity.
In contrast, peaceful trade with the former enemy would have allowed both nations to specialize, trade, and prosper. The wealth gained through peaceful trade exceeds the potential gains from warfare (Angell, 1911; Pinker, 2011).
The Creation of Specialized Interdependence
Perhaps most importantly, civilized economies create specialized interdependence. Individuals become dependent on others not just for goods but for their specific expertise and role:
- The modern farmer depends on agricultural scientists, who develop improved crops and techniques
- The patient depends on physicians and researchers who develop medical treatments
- The student depends on teachers and professors
- The citizens depend on engineers who maintain infrastructure, electricians who provide power, and communicators who maintain information systems
This specialized interdependence means that individuals have a strong incentive to maintain the systems and relationships that make their specialization valuable. A physicist’s knowledge is valuable in a society with institutions that value scientific advancement. In a society destroyed by war, the physicist’s knowledge becomes worthless. A surgeon’s skills are valuable in a society with hospitals and medical infrastructure. War that destroys hospitals destroys the value of surgical skill.
This creates a powerful disincentive against war. Unlike in tribal societies, where individuals might benefit personally from war’s spoils, in civilized societies, individuals benefit from the maintenance of peaceful, specialized systems of production and exchange.
Rule of Law: From War to Legal Resolution of Disputes
In tribal societies, Grotius noted, disputes arose, and when peaceful settlement failed, war ensued. War was the default mechanism for resolving disputes when negotiation failed. In civilized societies, systems of the rule of law have emerged to perform this dispute-resolution function.
The Emergence of Legal Systems
Legal systems develop to establish clear rules, adjudicate disputes, and enforce remedies without warfare. A well-functioning legal system allows parties in conflict to present their cases to a neutral authority (judge or court), which applies established rules to determine who is right and orders an appropriate remedy. This achieves the purposes that warfare once served—enforcement of rights, punishment of wrong, and reparation for injury—without the destruction and loss of life that warfare entails (Fuller, 1964).
The advantages of legal systems over warfare are substantial:
Precision and Clarity: Legal systems can establish precise rules. Rather than each dispute potentially escalating to warfare, rules define rights and obligations clearly. Parties understand beforehand what they can do and what they cannot do.
Neutrality: Courts are designed to be neutral between parties in dispute. Rather than parties fighting to determine who is stronger, courts apply the law to determine who is right. The party with the stronger legal argument prevails, not the party with more weapons.
Expertise: Judges and courts develop expertise in interpreting and applying the law. Over time, legal precedent develops—accumulated knowledge about how laws should apply to particular circumstances. This expertise leads to more consistent and just outcomes than would result from warfare.
Enforceability: Modern governments possess a monopoly on legitimate force. This means courts can enforce decisions without resorting to warfare. The losing party must comply; if they refuse, government force can enforce compliance. This makes warfare unnecessary to enforce court decisions.
Efficiency: Legal resolution of disputes is far more efficient than warfare. A lawsuit that lasts months is cheaper and faster than a war lasting years. We can devote the saved resources to productive purposes.
International Law and Inter-State Dispute Resolution
The emergence of international law, governing relations between nations, has been less complete in its parallelism with the emergence of the rule of law within nations. International law establishes rules for state behavior, creates mechanisms for peaceful resolution of disputes, and provides frameworks for dealing with violations of international agreements (Shaw, 2021).
Modern international institutions—including the United Nations, regional courts, arbitration systems, and treaty-based dispute resolution mechanisms—extend the logic of the rule of law to international relations. Rather than states settling disputes through warfare, they can bring cases before international courts or arbitration panels. While international law is less developed and less effectively enforced than domestic law, it provides mechanisms for peaceful dispute resolution that did not exist in earlier eras (Keohane, 1984).
The development of international law reflects recognition that even at the international level, peaceful legal resolution of disputes serves the interests of all parties better than warfare. Two nations that resolve a trade dispute through arbitration both benefit from the restoration of trade and certainty about rules. They both benefit compared to warfare, which destroys trade and economic relationships.
Why the Rule of Law Eliminates Organic Causes of War
The rule of law eliminates the organic causes of war identified by Grotius:
Self-Defense Remains: Legal systems still preserve the right to self-defense against actual aggression. If one party attacks another, self-defense is justified. But the threshold for genuine defense is clear—there must be an actual unprovoked attack.
Reparation Through Law: Rather than warfare to compel reparation, legal systems enforce payment of damages. A person wronged through theft or breach of contract can sue and recover. This achieves the goal of reparation without warfare.
Punishment Through Law: Rather than warfare to punish wrongdoing, legal systems prosecute and punish criminals and provide sanctions against violators. A nation that violates international agreements can face sanctions, international court proceedings, or diplomatic isolation. These remedies achieve the goal of enforcement without warfare.
Dispute Resolution: Rather than warfare to resolve disputes, legal systems adjudicate disputes. Two nations disputing territory, resources, or rights can bring cases before international courts rather than wage war.
The rule of law performs the functions that warfare once performed—enforcement of rights, punishment of wrong, reparation for injury, and dispute resolution—without the massive destruction that warfare entails. Therefore, in a civilization with a functioning rule of law, there is no material cause for war except in the narrow case of defense against unprovoked aggression.
What Defines “Civilization”: Integration Rather Than Conquest
The concept of “civilization” itself reflects this transformation. Historians and anthropologists use the term “civilized society” to describe societies that have transitioned from tribal to integrated political organization with rule of law. What makes a society civilized is not military power or cultural sophistication, but the establishment of peaceful coexistence among previously distinct groups (Keegan, 1993).
In this view, the defining characteristic of a civilized society is precisely that autonomous individuals from different tribes or ethnic groups who previously fought each other now live together peacefully under common law. They may maintain distinct cultural identities while accepting common political authority and legal rules. They compete economically but do not wage war (McNeill, 1982).
This understanding of civilization has several implications:
The Historical Achievement: That people from different groups can live together peacefully without war is a remarkable historical achievement. It required the development of legal systems, the growth of empathy and understanding across group boundaries, and the establishment of institutions that prioritize inclusion over exclusion. The fact that this is possible—that humans can transcend tribal warfare—is historically significant.
Vulnerability of Civilization: Civilization is not inevitable or irreversible. It depends on the maintenance of the rule of law, on continued investment in integrating diverse groups, and on the rejection of appeals to tribal or ethnic violence. When the rule of law breaks down, when institutions fail, and when leaders appeal to tribal or ethnic identity against the broader community, civilization itself faces a threat. Genocides and civil wars show how quickly civilization can collapse (Payne, 2004).
Possibility of Expansion: If civilization means peaceful coexistence of different groups under the rule of law, then we can expand the concept beyond current national borders. Nations sharing an ecosystem or economic region can integrate themselves into a civilized system. Nations can extend “civilization”—understood as peaceful coexistence based on law rather than force—by creating international institutions and legal frameworks that allow diverse nations to resolve disputes peacefully while maintaining autonomy in cultural and political matters.
If civilization means peaceful coexistence of different groups under the rule of law, then we can expand the concept beyond current national borders.
Creating a Cosmopolitan Civilization: Beyond National Boundaries
Extending the logic of civilization internationally is possible. Just as organic solidarity replaced mechanical solidarity within nations, it can also replace it internationally. The development of international law, international institutions, and economic interdependence has begun this process. But it remains incomplete.
One proposal to advance cosmopolitan civilization is the creation of special zones for people separated by national boundaries but sharing ecosystems or economic regions. For example, the Mediterranean region shares a climate, ecosystems, and economic interests. A Mediterranean civilization zone with relaxed borders, allowing for migration and free movement of people and goods, would extend the benefits of civilized society to a broader region.
Similarly, relaxing exit and entry criteria more broadly would allow the natural processes of civilization—migration, adaptation, and integration—to function. Rather than insisting on strict national borders and limiting movement of people, nations could allow more open movement while maintaining the rule of law. Migrants would adopt the legal norms of their new community through integration while cultural identity issues take their natural course without political intervention. Over time, this would create more integrated international societies (Keohane, 1984).
Just War Theory: When War Remains Justified
Despite the elimination of organic material causes of war in civilized society, just war theory still identifies limited circumstances in which war may be justified. This paper argues for a restricted interpretation of just war theory in a civilized context.
Traditional Just War Theory
Just war theory, developed by Augustine, Grotius, Aquinas, and contemporary philosophers, identifies three stages of warfare:
Jus ad Bellum (Justice of Going to War): This concerns criteria that people must meet before going to war. Traditional criteria include just cause, right intention, proper authority, reasonable chance of success, last resort, and proportionality. Essentially, before waging war, leaders must demonstrate that a serious injustice exists, cannot be remedied by peaceful means; that war has a reasonable chance of success, and that the benefits will outweigh harm (Walzer, 2006).
Jus in Bello (Justice in Conducting War): This concerns how war should be conducted. Traditional principles include proportionality (not using excessive force), discrimination (distinguishing combatants from civilians), and the prohibition of prohibited weapons. Essentially, even in a just war, combatants have obligations to minimize harm to civilians and use only necessary force (Walzer, 2006).
Jus post Bellum (Justice After War): This concerns the peace settlement after war. Traditional requirements include discrimination in punishment (punishing those responsible rather than the entire population), proportionality in punishment (not excessive), right intention (genuinely trying to establish just peace), and proper authority for the peace terms. Essentially, victors have an obligation to establish a just peace rather than impose vengeful or exploitative settlements (Walzer, 2006).
Application to Civilized Society
A civilized society must understand the criteria for a just war within the context of the rule of law and the elimination of material causes of war.
The Threshold for Just Cause Must Be High: In tribal society, scarcity and resource competition provided material causes for war. In civilized society, these causes no longer exist. Therefore, the threshold for demonstrating that war is necessary should be high. The burden of proof rests with those arguing that war is required. Peaceful, legal and diplomatic alternatives must be exhausted.
Self-Defense Remains Justified: Grotius’s first justifiable cause of war—self-defense against injury—remains valid. A nation attacked without provocation may rightfully defend itself. The principle of self-defense doesn’t demand a nation wait for an attack. However, the threat must be genuine and imminent, not speculative or remote.
Defense Against Genocide and Mass Atrocities: An extension of self-defense is intervention to stop ongoing genocide or mass atrocities. Just as self-defense is justified when one faces injury, intervention to stop genocide against others may be justified as a defense of humanity and human rights (Bass, 2008). International law has moved toward recognizing humanitarian intervention as justified under narrow circumstances.
Removal of Oppressive Government: A second justifiable cause of war in civilized society is the removal of an undemocratic government that denies people the ability to remove it through electoral systems. This requires careful articulation.
A government that is undemocratic—that is, one that does not allow free elections, free speech, or political participation—denies its people’s fundamental rights of citizens in civilized society. It perpetuates tyranny through manipulation and force. When such a government prevents its people from removing it through electoral means—through fraud, violence, or suppression of opposition—military intervention to remove it may be justified.
The justification is: the rule of law defines civilized society and by the ability of citizens to remove government through electoral processes. A government that prevents this denies the defining characteristic of civilization. Military intervention to restore the possibility of free elections and democratic governance serves to extend civilization—the possibility of peaceful self-governance under law.
However, this justification is narrow and subject to strict limitations:
- The government must be demonstrably undemocratic and oppressive. Mere disagreement with government policy is not sufficient. The government must deny basic freedoms and prevent electoral removal.
- The intervening nation must have legitimacy to intervene. Intervention by an external power should occur only with the authorization of international bodies or regional organizations, not unilaterally. Powerful nations can easily corrupt unilateral intervention into imperialism.
- The goal must genuinely be restoration of democratic governance, not extraction of resources or imposition of the intervening nation’s ideology. Intervention is not justified to impose particular economic systems or cultural practices, but to restore the possibility of self-determination through free elections.
- The intervening nation must genuinely leave. The intervening nation must withdraw and let the nation govern itself after the democratic elections are established, even if the people elect leaders or policies that the intervening nation disagrees with.
What Is Not Justifiable in Civilized Society
Several causes of war that were once justifiable under Grotius’s framework are no longer justifiable in civilized society:
Territorial Conquest and Acquisition of Resources: In tribal society, conquest of territory was a material necessity for survival. In a civilized society, with functioning international trade and law, nations do not need to conquer territory to access resources. Trade allows nations to obtain resources more cheaply and efficiently than conquest does. Therefore, territorial conquest cannot be justified as a just cause of war in civilized society.
Punishment of Nations (as distinct from removal of oppressive government): Grotius justified war to punish serious wrongdoing. In a civilized society, international law provides mechanisms for prosecution and punishment without warfare. International courts can try nations, and international mechanisms can sanction them, holding them accountable through law. Warfare as punishment is no longer necessary and should not be justified.
Preemptive War Based on Speculative or Remote Threats: While preemptive self-defense may be justified against imminent threats, war based on speculative or remote threats is not justified. If a nation might someday pose a threat, that does not justify war now. This was the rationale for the 2003 invasion of Iraq—the claim that Iraq might develop weapons of mass destruction. This did not meet the standard of imminent threat and violated the principle that peaceful alternatives should be exhausted.
Defining Self-Defense: What Justifies War in Civilized Society
Given the analysis above, self-defense remains the primary justifiable cause of war in civilized society. It is important to define self-defense carefully.
Defense Against Unprovoked Aggression
The clearest case of justified self-defense is defense against unprovoked military aggression. If one nation attacks another without justification, the attacked nation may defend itself. Using force to stop an aggressor and restore peace is justified. However, once the aggression stops, self-defense no longer justifies further warfare. The goal of self-defense is to end the aggression, not to punish or subjugate the aggressor.
Defense of Democratic Self-Determination
A related but distinct form of self-defense is defense of the ability of a people to determine their own government. If external forces attempt to impose a rule on a people against their will, the people can understand resistance to this imposition as self-defense. Just as individuals have a right to defend themselves against assault, peoples have the right to defend their self-determination against external conquest or domination.
This is the justification for supporting independence movements against colonial powers. It is also the justification for nations defending themselves against hostile takeover or forced incorporation into another nation.
Humanitarian Defense: Stopping Genocide
An extension of self-defense is the right to defend humanity against genocide and mass atrocities. Just as an individual witnessing violence against another has some obligation to intervene, nations witnessing genocide have some obligation to intervene to stop it (Bass, 2008).
This remains controversial—how far does the obligation extend? Must a nation sacrifice its own soldiers to stop genocide in another nation? At what point does humanitarian obligation become imperialism disguised as humanitarian intervention? These are tough questions with no simple answers. However, international law increasingly accepts that armed intervention may be justified because genocide and mass atrocities are sufficiently grave wrongs.
Why Civilized Nations Should Be Reluctant to Wage War
Even when war may be technically justified, civilized nations should be extremely reluctant to wage war. Several reasons support this reluctance:
The Assumption of Peaceful Resolution
When the rule of law exists and peaceful mechanisms for dispute resolution have been developed, people strongly assume that disputes should be resolved peacefully. The burden rests with those arguing for war to show convincingly that peaceful alternatives have been exhausted and that war is necessary.
In tribal society, people arguing for peace had to explain why they should not address a material injury through warfare. In civilized society, the assumption reverses: disputes should be peaceful unless war is clearly necessary.
The Uncertainty of Outcomes
Wars are unpredictable. Plans developed before a war often prove wrong once fighting begins. Leaders overestimate their nation’s strength and underestimate the enemy’s strength. Unintended consequences multiply. A brief war often becomes prolonged. War intended to be limited expands. The costs of achieving them (Mueller, 1989) erase supposed gains in military victory.
In civilized society, where peaceful alternatives exist, this unpredictability is a sound reason to avoid war. The costs and risks of war are often greater than any potential benefit.
The Moral Costs of Warfare
Warfare involves killing, injury, trauma, and destruction. These are grave harms that civilized society generally recognizes as evils to be avoided when possible. Even when warfare is justified, these harms should weigh heavily in decisions about whether war is necessary.
This is particularly acute regarding civilian casualties. In modern warfare, a high percentage of deaths are non-combatants—people not engaged in fighting. These deaths are a tragic waste, and their prevalence in modern conflict should make modern societies deeply reluctant to wage war.
The Precedent of Using Force to Solve Problems
When nations wage war to resolve disputes, they establish a precedent that force is an acceptable means of resolving conflicts. This precedent makes future disputes more likely to involve force. It normalizes violence as a political tool.
Conversely, nations that consistently resolve disputes peacefully establish a precedent that peaceful resolution is the norm. Citizens and leaders become accustomed to peaceful settlements. This reduces the likelihood of force in future disputes.
International Law and the Future of Civilization
The long-term trajectory of human development has been toward increasing integration and decreasing reliance on warfare. Tribal warfare gave way to national states and interstate law. Interstate law created a framework for peaceful resolution of disputes. Modern international institutions extend these frameworks globally. The future development of civilization lies in further integration and strengthening of the rule of law internationally.
Strengthening International Law
International law remains weaker than domestic law. Nations sometimes violate international agreements. International courts have limited enforcement mechanisms. International institutions often lack the authority to enforce their decisions. Strengthening international law—making it clearer, more enforceable, and more legitimate—would reduce incentives for nations to resort to warfare.
This could involve:
- Establishing more effective international dispute resolution mechanisms.
- Strengthening international criminal courts and the prosecution of violations of international law.
- Creating international institutions with greater authority and legitimacy.
- Developing international standards for resolving disputes over resources, territory, and rights.
- Establishing mechanisms for collective security that make unilateral aggression costly.
Reducing the Barriers Between Peoples
Civilization, as defined in this paper, involves the integration of previously distinct peoples under the rule of law. Reducing barriers between peoples can further this integration.
- Allowing greater freedom of movement and migration
- Facilitating trade and economic integration
- Promoting cultural exchange and understanding
- Creating cross-border institutions and communities
- Developing a shared identity as members of a broader human community
As people become more connected to each other—through family relationships, friendships, economic ties, and shared institutions—warfare becomes less likely. It is difficult to wage war against people one knows, respects, and depends on economically and personally.
Addressing the Root Causes of Modern Conflict
While this paper has argued that material scarcity no longer justifies war in civilized society, modern conflicts often arise from other causes: ethnic tensions, religious conflicts, struggles for power and dominance, and competition for political control. Addressing these requirements:
- Education that promotes understanding across group boundaries
- Political institutions that fairly represent diverse groups
- Economic development that reduces extreme poverty (though wealth inequality remains controversial)
- Conflict resolution mechanisms that allow grievances to be addressed without violence
- Accountability for past wrongs that have generated resentment
Conclusion: Toward a Civilized International System
This paper argues that the development of civilized society systematically eliminated material and organic causes of war. The two primary conditions that made war inevitable in tribal and barbarian societies—mechanical solidarity and dependence on natural resources—no longer exist in modern civilized nations.
Organic solidarity has replaced mechanical solidarity based on the division of labor and economic interdependence. When autonomous individuals from different backgrounds live together and depend on each other economically, warfare between them becomes irrational and destructive.
Interdependence has replaced dependence on natural resources for survival among specialized producers. In civilized economies, survival and prosperity depend on maintaining relationships of trade and specialization, not on conquest. Warfare disrupts these relationships and thereby undermines the prosperity of all parties.
Systems of rule of law have emerged to perform the dispute-resolution functions that warfare once performed. People can enforce rights, remedy wrongs, and resolve disputes without warfare. Therefore, the material justifications that Grotius identified for warfare are no longer necessary.
Yet, people have not eliminated war. Wars continue to occur, and people find new justifications. This is not because of material causes of war persist—they do not—but because war persists for other reasons: failures of institutions, appeals to tribal or ethnic identity, competition for power, ideological conflicts, and the human capacity for violence.
The challenge for contemporary civilization is to strengthen the legal and institutional frameworks that can prevent war while respecting the autonomy and dignity of diverse peoples. This requires a commitment to:
- Rule of Law: Continuing to develop and strengthen legal systems and institutions that can peacefully resolve disputes and enforce justice
- Economic Integration: Promoting trade, movement of people, and economic cooperation that creates mutual dependence and shared an interest in peace
- Education: Teaching citizens to value peace, to understand diverse perspectives, and to resolve conflicts through dialogue rather than violence
- Democratic Governance: Ensuring that people have a voice in governance and the ability to remove governments through peaceful means, reducing the incentive to resort to violence
- International Community: Building stronger international institutions and norms that make cooperation preferable to conflict
In this context, people should understand war not as a necessary feature of human society but as a failure of institutions and relationships. When civilized societies resort to war, they do so not because war is necessary but because they have failed to maintain the legal, economic, and political relationships that make peace possible.
The justifications for war in civilized society are narrow: genuine self-defense against unprovoked aggression and, in limited circumstances, removal of governments that prevent their people from removing them through electoral means. People should resolve all other conflicts peacefully. Civilized nations should approach even justified wars with reluctance, as a last resort when all peaceful alternatives have been exhausted.
The future of civilization depends on continuing to strengthen the institutions and relationships that make peace the rational choice. As the world becomes more interconnected, more economically integrated, and more institutionally developed, the material basis for warfare continues to diminish. The challenge is to ensure that legal, political, and moral development keeps pace with material development, so that humanity can transcend warfare and create a genuinely global civilization in which law resolves disputes rather than by force.
12. References
Acemoglu, D., & Robinson, J. A. (2012). Why nations fail: The origins of power, prosperity, and poverty. Crown Business.
Angell, N. (1911). The great illusion: A study of the relation of military power to national advantage. G. P. Putnam’s Sons.
Augustine, S. (1984). The city of God against the pagans (R. W. Dyson, Ed. & Trans.). Cambridge University Press. (Original work published ca. 427)
Bass, G. J. (2008). Freedom’s battle: The origins of humanitarian intervention. Knopf.
Durkheim, É. (1984). The division of labor in society (W. D. Halls, Trans.). Free Press. (Original work published 1893)
Fuller, L. L. (1964). The morality of law (Rev. ed.). Yale University Press.
Grotius, H. (2005). The rights of war and peace (R. Tuck, Ed.). Liberty Fund. (Original work published 1625)
Keegan, J. (1993). A history of warfare. Knopf.
Keohane, R. O. (1984). After hegemony: Cooperation and discord in the world political economy. Princeton University Press.
McNeill, W. H. (1982). The pursuit of power: Technology, armed force, and society since A.D. 1000. University of Chicago Press.
Mueller, J. E. (1989). Retreat from doomsday: The obsolescence of major war. Basic Books.
Payne, S. G. (2004). Fascism: Comparison and definition. University of Wisconsin Press.
Pinker, S. (2011). The better angels of our nature: Why violence has declined. Viking.
Rawls, J. (1999). A theory of justice (Rev. ed.). Harvard University Press.
Sen, A. (1999). Development as freedom. Oxford University Press.
Shaw, M. N. (2021). International law (9th ed.). Cambridge University Press.
Smith, A. (1976). An inquiry into the nature and causes of the wealth of nations (E. Cannan, Ed.). University of Chicago Press. (Original work published 1776)
Walzer, M. (2006). Just and unjust wars: A moral argument with historical illustrations (4th ed.). Basic Books.