Chapter 51

The Ethics of War and Pacifism

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War is among humanity’s oldest and most destructive practices. It arises when negotiation and diplomacy collapse, when survival feels threatened, or when ambition drives conquest. Yet war does not occur in a moral vacuum. Even in the midst of violence, humans wrestle with ethical questions: When is it right to fight? What limits should govern combat? And can war ever be truly just? The ethics of war, examined across philosophy, religion, and international law, reflects the tension between necessity and morality in human affairs.

Just War Theory: The Search for Moral Boundaries

The dominant framework for assessing the ethics of war is the “just war theory”, developed by thinkers such as Augustine (4th century CE) and Thomas Aquinas (13th century CE). Just war theory divides ethical concerns into two categories:

  • Jus ad bellum (justice of war): The criteria for deciding when going to war is just, such as self-defense, last resort, legitimate authority, and proportionality. For instance, resisting invasion is often cited as a legitimate cause.
  • Jus in bello (justice in war): Standards for conduct during war, including discrimination (distinguishing combatants from non-combatants) and proportionality (avoiding excessive force relative to objectives).

Later thinkers, such as Hugo Grotius (17th century), expanded this framework, laying the foundation for international law. The Geneva Conventions (20th century) represent modern attempts to codify these ethical principles in binding legal agreements.

Realism: Ethics as Irrelevant in War

In contrast, political realists argue that war is not subject to morality. Thucydides, in The History of the Peloponnesian War, famously depicted the “Melian Dialogue,” where Athenians declared, “The strong do what they can, and the weak suffer what they must.” From this perspective, war is governed by power, not ethics. Realism maintains that survival and national interest override moral considerations. Modern realists, such as Hans Morgenthau, echo this view, suggesting that moralizing about war often disguises raw self-interest. The actions of the U.S. Executive Branch of government in 2026 exemplify this perspective.

Pacifism: The Rejection of War

At the opposite pole is pacifism, the belief that war is never morally justifiable. Religious traditions such as early Christianity, Buddhism, and Jainism have promoted nonviolence as an absolute value. Modern pacifists, including figures like Mahatma Gandhi and Martin Luther King Jr., argue that nonviolent resistance is both morally superior and strategically effective. However, pacifism faces criticism for being impractical in the face of aggression - such as Nazi Germany’s expansion in the 1930s.

On a personal note, when I sat before the San Jose, California, draft board in 1970 and pleaded my case for Conscientious Objector status, I claimed to be an absolute pacifist. I knew that solely opposing the Vietnam War (which I started doing publicly in 1963) wouldn’t have led to approval of my submittal. Fortunately, they didn’t press for an answer to the hypothetical question about what my stance would have been in 1941. Yes, several of my mother’s close friends chose jail then instead of taking up arms, but I have no idea if that would have been my choice. Fortunately, my 1970 request was granted; I didn’t have to go to jail, and I served my country for two years counseling troubled youth in the States as a CO.

Ethical Dilemmas in Modern Warfare

The nature of war has changed dramatically, raising new ethical challenges:

  • Civilian Casualties and Technology. Drone strikes, aerial bombings, and cyberattacks blur the line between combatants and civilians. Ethical frameworks must adapt to technologies that increase both precision and the potential for indiscriminate harm.
  • Weapons of Mass Destruction. Nuclear, chemical, and biological weapons raise profound moral questions because their destructive capacity violates proportionality and discrimination. The bombings of Hiroshima and Nagasaki remain subjects of heated ethical debate.
  • Humanitarian Intervention. Should nations intervene militarily to stop genocide or mass atrocities, as in Rwanda (1994) or Bosnia (1990s)? Intervention may save lives but also risk unintended consequences and violations of sovereignty.
  • Terrorism and Asymmetric Warfare. Non-state actors often exploit civilian populations, making traditional ethical distinctions harder to apply. Counterterrorism strategies, in turn, risk overreach and abuse.

Toward a Global Ethical Framework

While war may never be eliminated entirely, efforts to constrain it through shared ethics have advanced. The United Nations Charter (1945) prohibits aggressive war, permitting force only in self-defense or under UN Security Council authorization. The Geneva Conventions (1949) protect civilians and prisoners of war. Philosophers such as Michael Walzer (Just and Unjust Wars, 1977) argue that moral reasoning remains vital in holding states and militaries accountable.

At the same time, critics warn that ethical rhetoric is often used selectively, with powerful nations justifying their wars as “just” while condemning their enemies. This underscores the need for vigilance in ensuring that ethical principles are applied universally rather than as tools of political convenience.

To summarize…

The ethics of war embodies a deep paradox: war is both the breakdown of morality and the arena where moral questions are most urgent. Just war theory provides guidance for when and how wars might be fought ethically, while pacifism challenges us to imagine a world without war. Realism reminds us of the harsh realities of power, but international law and human conscience insist that even in war, limits matter. The future of ethical warfare depends not only on rules and treaties but also on the collective will to recognize shared humanity - even in conflict.

A world without war is an aspect of the Utopian ideal. Let's next explore that subject.



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