What war is, why wars happen, how laws try to limit the harm of war, and how societies build lasting peace.
Young children can begin to understand peace and conflict through their own experience of disagreements — with friends, siblings, and classmates. Children do not need the word 'war'. But they can learn the basic principles: disagreements are normal and can be worked out; hurting people is not a good way to solve problems; strong people help others feel safe; peace is something we build together, not just the absence of fighting. These early habits of conflict resolution are the foundation of peaceful societies. Countries that handle conflicts well at every level — in homes, schools, workplaces, courts, and between nations — are far less likely to end up at war. Teaching children to handle conflict with words, empathy, and fairness is one of the most important things a school can do. No materials are needed — this lives in everyday classroom culture.
The strongest person always wins.
In the short term, a bigger or louder person may get their way. But that is not the same as winning. A child who takes a toy by grabbing it will probably not have friends who want to play with them. A country that takes something by force will probably make many enemies. Real strength is being able to stop a fight, share fairly, and work things out. Anyone can be strong in this way — not just the biggest or the loudest.
Peace just means no fighting.
Real peace is more than just quiet. A place where one person is afraid of another is not really peaceful — even if there is no loud fight. Real peace means everyone feels safe, everyone is treated fairly, and people talk to each other. Peace is built with kindness, trust, and fair rules. It is something we make together, not something that just happens.
War is organised violence between groups, usually between countries or within countries, in which many people are killed or harmed. War is one of the oldest and most destructive human activities. The 20th century alone saw two World Wars, dozens of other major conflicts, and an estimated 100-150 million deaths from war and war-related causes. Why wars happen is one of the hardest questions in political science.
Disputes over territory; disputes over resources (oil, water, minerals); disputes over power and influence; ethnic or religious conflict; ideological disagreement; defence against attack; the ambition of individual leaders. Usually, several causes combine. Wars rarely have a single cause, and the stated reasons are often different from the real ones. The cost of war is enormous. Millions are killed, directly and indirectly. Many more are wounded physically and psychologically. Millions become refugees, fleeing destroyed homes. Infrastructure — roads, schools, hospitals, water systems — is destroyed.
Children grow up in trauma.
Environmental damage is often severe. The effects persist for generations: children of war survivors carry the trauma; destroyed economies take decades to rebuild; broken societies struggle to heal.
Despite the violence, societies have long tried to set limits on war. International humanitarian law (IHL) — most fully set out in the Geneva Conventions (1949) and their Additional Protocols — establishes rules that apply even during armed conflict.
Protect civilians (who should never be targeted); treat prisoners of war humanely; care for the wounded; do not attack hospitals, schools, or cultural sites; do not use banned weapons (chemical, biological, certain explosive weapons). These rules are backed by international courts. The International Criminal Court (established 2002) prosecutes war crimes, crimes against humanity, and genocide. Earlier tribunals (Nuremberg after WWII, Yugoslavia, Rwanda, Sierra Leone) prosecuted specific conflicts.
For centuries, thinkers have tried to distinguish wars that might be morally acceptable from those that clearly are not. The 'just war' tradition, running from Augustine (5th century) through Aquinas, Grotius, and modern writers, developed criteria. A war might be just if: the cause is legitimate (self-defence, protection of civilians from mass atrocity); all other options have been tried; it is declared by proper authority; the likely harm is not greater than the harm it prevents; civilians are not deliberately targeted. Critics note that these criteria have been used to justify many wars that later look unjust. Pacifism is an alternative view — that all war is wrong and non-violent alternatives should always be sought.
International law strongly favours peaceful resolution of disputes. The UN Charter (1945) commits member states to 'settle their international disputes by peaceful means'.
Negotiation between parties; mediation by a neutral third party; arbitration with a binding decision; international courts (the International Court of Justice handles disputes between states). Many disputes are resolved this way without war. The UN also provides peacekeeping — sending international forces to help maintain ceasefires after fighting ends.
Ending fighting is not the same as building peace. After wars, societies face the task of peacebuilding — rebuilding institutions, repairing infrastructure, addressing the causes that led to war, helping survivors heal, and preventing a return to violence. Historically, some wars have produced lasting peace (Western Europe after 1945); others have seen repeated conflict (Afghanistan, Congo, Sudan). Successful peacebuilding usually requires addressing real grievances, building trust across divided groups, and creating institutions that let disputes be handled peacefully.
This is a specifically sensitive topic. Students may have family connections to current or past conflicts; some may have refugee backgrounds. Present the topic honestly but with care. Avoid choosing sides in current political conflicts; focus on principles and historical cases that students can examine with some distance.
War always makes one side the winner and the other the loser.
In reality, almost everyone loses in war. The 'winning' side may achieve its military goals but still suffer huge losses — dead soldiers, destroyed cities, trauma, economic damage, bitter enemies. The 'losing' side suffers even more. Civilians on both sides usually suffer most. Even so-called 'victories' often bring problems that last for decades: refugees, unresolved hatred, revenge cycles. The idea of a clean win and loss hides the enormous cost that war imposes on nearly everyone involved.
Ordinary people have no role in war and peace — these are matters for governments.
Governments start and end wars, but wars depend on ordinary people in many ways. Soldiers are ordinary people. War workers in factories are ordinary people. Voters who support or oppose war are ordinary people. Refugees are ordinary people. Peacemakers in communities are ordinary people. History shows that ordinary people have often prevented wars by refusing to fight, ended wars by protesting, and built peace by reaching out to former enemies. Every war is made possible by many choices; every peace is built by many people.
The laws of war do not matter because they are often broken.
Laws of war are broken in nearly every conflict — this is true. But the same is true of domestic laws: murders happen even though murder is illegal. We do not conclude from this that laws against murder are useless. Laws of war shape behaviour even when they do not prevent all violations. Most soldiers most of the time follow the rules. War criminals are sometimes prosecuted, creating real consequences. And the rules give us a language for judging what happens — without the rules, there would be no difference between killing a combatant in battle and massacring civilians. The rules matter precisely because the alternative is worse.
War and peace are among the deepest questions of political life, and the field of international relations, security studies, and peace studies contains enormously rich traditions.
Political scientists have studied this for generations. Realist theories (Hans Morgenthau, Kenneth Waltz, John Mearsheimer) emphasise power politics — states fight over relative power in an anarchic international system. Liberal theories (Michael Doyle, Immanuel Kant's 'Perpetual Peace') emphasise how democratic institutions, trade, and international organisations can reduce war. Constructivist theories emphasise ideas, identities, and norms. Psychological theories emphasise misperception and leaders' cognitive biases. Domestic theories emphasise how internal politics (scapegoating, diversionary wars, ethnic divisions) produce conflict. Economic theories emphasise resources, trade disputes, and rent extraction. Most serious scholars believe multiple factors combine in most wars. James Fearon's 'Rationalist Explanations for War' (1995) influentially asked why rational states ever fight — given that negotiated settlements should be cheaper — and identified information problems, commitment problems, and issue indivisibilities as key causes.
Augustine of Hippo (5th century) first developed a systematic Christian ethics of war. Thomas Aquinas and later Francisco de Vitoria and Hugo Grotius developed the tradition further. Modern just war theory (Michael Walzer's 'Just and Unjust Wars', 1977) is secular and widely influential. Just war divides into jus ad bellum (when war is justified) and jus in bello (how war may be fought).
Just cause (usually limited to self-defence or defence of others from grave harm); legitimate authority; right intention; reasonable chance of success; proportionality; last resort.
Discrimination (civilians must not be targeted); proportionality; no use of banned methods or weapons. Critics include pacifists (who reject all war), realists (who see just war as illusion), and those who argue the tradition has been manipulated to justify unjust wars.
The Geneva Conventions of 1949 are the foundation. Four conventions cover wounded soldiers on land, wounded soldiers at sea, prisoners of war, and civilians. Additional Protocols (1977, 2005) extend protection.
Distinction (civilians from combatants); proportionality (expected civilian harm must not exceed military advantage); precaution (must take steps to minimise civilian harm); humanity (unnecessary suffering prohibited); prohibition of specific weapons (chemical, biological, anti-personnel mines, cluster munitions in most countries). The International Committee of the Red Cross (ICRC) is the designated guardian of IHL. Customary IHL binds states even without specific treaty ratification. The UN system: the UN Charter (1945) created the current international order.
Article 2(4) prohibits the threat or use of force by states except in limited circumstances. Article 51 preserves the right of individual and collective self-defence. Chapter VII allows the Security Council to authorise collective action against threats to peace. Five permanent members of the Security Council (US, UK, France, Russia, China) have veto power — which has often paralysed the system. UN peacekeeping has deployed forces to over 70 missions since 1948. Record is mixed — some successes (Namibia, El Salvador), some failures (Rwanda, Srebrenica).
The Nuremberg and Tokyo tribunals after WWII established that individuals could be prosecuted for international crimes. The UN ad hoc tribunals for former Yugoslavia (ICTY, 1993-2017) and Rwanda (ICTR, 1994-2015) prosecuted perpetrators of genocide, war crimes, and crimes against humanity. The International Criminal Court (ICC), created by the Rome Statute (2002), is the first permanent international criminal court. It has 124 state parties; the US, Russia, China, India, and Israel have not joined. The ICC has prosecuted cases mostly from Africa; it issued an arrest warrant against Russian President Putin in 2023 for the unlawful deportation of Ukrainian children. Political controversies over selectivity and enforcement remain significant.
Pacifism is the view that all war or all killing is wrong. Forms include absolute pacifism (no violence ever), consequentialist pacifism (war causes more harm than good), and religious pacifism (specific faith traditions). Nonviolence as a political strategy (Gandhi, Martin Luther King Jr., Gene Sharp) goes further, arguing that systematic nonviolent action is often more effective than war at bringing about political change. Erica Chenoweth and Maria Stephan's research (discussed in the assembly topic) found peaceful resistance succeeded roughly twice as often as armed resistance at achieving political goals between 1900-2006.
The discipline of studying how lasting peace is achieved after conflict. Johan Galtung distinguished 'negative peace' (absence of war) from 'positive peace' (absence of structural violence and presence of justice).
Security sector reform; disarmament, demobilisation, and reintegration (DDR) of former fighters; truth commissions; transitional justice; reconstruction; political reform; economic development; reconciliation. The UN Peacebuilding Commission (2005) coordinates international efforts. Mixed results — some successes (Mozambique, Timor-Leste), some ongoing struggles (DRC, Afghanistan, South Sudan, Yemen).
The nature of war has changed significantly. Interstate wars have become less frequent; civil wars and internal conflicts have become more common. Non-state actors (insurgent groups, militias, criminal organisations, terrorist groups) play larger roles. Cyber warfare has emerged as a new domain. Drones and autonomous weapons raise new questions. Climate change drives new conflicts. Private military companies (Wagner, Blackwater/Academi) blur state boundaries.
Russia-Ukraine (since 2022); Israel-Gaza and broader Middle East tensions; Sudan civil war; Myanmar civil war; Ethiopia's Tigray conflict aftermath; multiple ongoing conflicts in Sahel, DRC, and Yemen. The Russia-Ukraine war has been the largest interstate war in Europe since WWII. The Geneva Conventions framework faces real stress from these conflicts.
In a world of ongoing conflicts, students may have strong views, direct experience, or family connections. Be careful about taking sides on current political conflicts. Focus on principles, historical cases, and the frameworks designed to limit war's harm.
Wars are usually caused by a single obvious factor.
Serious analysis consistently shows that most wars have multiple interacting causes. World War I combined alliance systems, militarism, nationalism, economic competition, and specific triggers. Civil wars typically involve structural factors (inequality, weak institutions, ethnic divisions) alongside proximate triggers. James Fearon's work showed that even 'rational' state decisions to go to war usually involve information problems, commitment problems, or issue indivisibilities — not single obvious causes. Simplistic single-cause explanations miss how conflicts actually develop and make prevention harder.
Rules of war only bind those who accept them — they are irrelevant to rogue states or non-state actors.
International humanitarian law is legally binding on all parties to armed conflict, including non-state armed groups. Common Article 3 of the Geneva Conventions applies specifically to non-international armed conflicts. Customary IHL applies regardless of treaty ratification. In practice, enforcement varies, but many non-state groups have accepted IHL standards (either because of legitimacy concerns, because they wish to avoid prosecution, or because they share the underlying values). The ICC has prosecuted both state actors and non-state actors (including leaders of the Lord's Resistance Army and other armed groups).
Winning a war solves the underlying problem.
Military victory rarely resolves the political issues that caused a war. After World War I, the harsh peace treaty on Germany contributed directly to World War II. After the US invaded Iraq and overthrew Saddam Hussein in 2003, political and sectarian conflicts led to continued violence for years. Military outcomes create conditions for political settlement — they do not substitute for it. Sustained peace requires addressing the political, economic, and social issues underlying the conflict, not just military success.
Peacekeeping missions are generally ineffective and a waste of resources.
Peacekeeping has a mixed record but significant successes. Rigorous research by scholars like Virginia Page Fortna shows that peacekeeping missions significantly increase the chances that peace will hold after a civil war. Successes include Namibia, El Salvador, Mozambique, and Timor-Leste. Failures (Rwanda, Srebrenica) often involved missions with inadequate mandates or resources. The lesson is not that peacekeeping fails but that specific mission designs succeed or fail based on factors like political backing, resources, mandate, and host-country conditions.
Key texts for students: Michael Walzer, 'Just and Unjust Wars' (1977) — the classic modern treatment of just war theory. Immanuel Kant, 'Perpetual Peace' (1795) — foundational liberal peace theory. Carl von Clausewitz, 'On War' (1832) — still essential for understanding war's nature. Hannah Arendt, 'On Violence' (1970). Margaret MacMillan, 'War: How Conflict Shaped Us' (2020) — accessible overview. For specific wars: Christopher Clark, 'The Sleepwalkers' (2013) on WWI origins; Ian Kershaw on WWII. For just war theory critics: Michael Walzer himself on modern challenges; James Turner Johnson's work. For pacifism and nonviolence: Gene Sharp, 'The Politics of Nonviolent Action' (1973); Erica Chenoweth and Maria Stephan, 'Why Civil Resistance Works' (2011). For IHL: any recent ICRC publication; Gary Solis, 'The Law of Armed Conflict' (2010). For peacebuilding: Roland Paris, 'At War's End' (2004); Virginia Page Fortna's work on peacekeeping. International bodies: ICRC (icrc.org); UN Office for the Coordination of Humanitarian Affairs; Peacekeeping missions map (peacekeeping.un.org); International Criminal Court (icc-cpi.int). Data sources: Uppsala Conflict Data Program (ucdp.uu.se) tracks ongoing conflicts; Correlates of War Project (correlatesofwar.org); Stockholm International Peace Research Institute (sipri.org) for military expenditure and arms trade.
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