The Ethics of War: Exploring Just War Theory in a Fractured World
The Weight of War
In a world simmering with conflicts: Israel and Iran, Gaza, Ukraine and Russia, China and Taiwan, Yemen, and crises across African nations, the question of whether war can ever be just looms large. The spectre of global escalation, potentially spiralling into a third world war, forces us to confront profound ethical dilemmas. When, if ever, is it permissible to engage in conflict that risks catastrophic consequences? Who holds the authority to make such momentous decisions? And what does history, through the lens of philosophy, teach us about the morality of war? Let me look into these questions, drawing on just war theory, historical precedents, and philosophical perspectives, while examining the current global landscape and the ominous possibility of a post-war world.
Just War Theory: A Moral Framework
Just war theory, a cornerstone of ethical discourse on conflict, seeks to reconcile the horrors of war with moral reasoning. Rooted in classical Greco-Roman thought and formalised by Christian theologians like Augustine of Hippo and Thomas Aquinas, it provides criteria to evaluate the justice of engaging in war (jus ad bellum) and the conduct within it (jus in bello). Augustine argued that war, though tragic, could be necessary to confront grave dangers, provided it aimed at restoring peace. Aquinas later refined this, emphasising legitimacy, proportionality, and necessity.
Modern formulations of just war theory outline key principles:
Just Cause: War must address a grave wrong, such as aggression or severe human rights abuses.
Legitimate Authority: Only recognised authorities, typically states, can declare war.
Right Intention: The aim must be justice, not vengeance or conquest.
Proportionality: The response must match the harm suffered, avoiding excessive destruction.
Last Resort: All peaceful alternatives must be exhausted.
Reasonable Chance of Success: War should not be futile, risking lives without achievable goals.
Discrimination: Combatants must distinguish between military targets and civilians.
Proportionality in Conduct: Actions in war must minimise harm relative to objectives.
Philosophers like Michael Walzer have updated these principles, arguing that wars can be just if they protect fundamental rights or resist aggression, but only under strict conditions. Yet, critics like Nolen Gertz question whether these criteria are too subjective, often manipulated to justify self-interest.
Historical Just Wars: Lessons from the Past
History offers contested examples of "just" wars. World War II is often cited as a paradigm: the Allies fought to halt Nazi aggression and genocide, meeting criteria of just cause and necessity. The liberation of Auschwitz-Birkenau, where 1.1 million were murdered, underscores the moral imperative to act against atrocities. Yet, even this war raises questions; Allied bombings of civilian cities like Dresden challenge the principle of discrimination.
The American Civil War, aimed at ending slavery, is another candidate, though its massive toll (over 600,000 deaths) tests proportionality. Conversely, wars like the Iraq Invasion of 2003, often justified under humanitarian or pre-emptive grounds, are widely critiqued as failing just war criteria due to questionable legitimacy and disproportionate outcomes.
Philosophers like John Rawls argue that just wars are rare, requiring clear moral imperatives and adherence to ethical conduct. Others, like Hannah Arendt, highlight the risk of moral rationalisations masking power or economic motives. The historical record suggests that while some wars may align with just war principles, their execution often blurs the line between justice and devastation.
Current Conflicts: Applying the Theory
Today’s conflicts test the boundaries of just war theory. In Ukraine, Russia’s invasion since 2022, escalating a conflict begun in 2014, has killed tens of thousands and displaced millions. Ukraine’s resistance is widely seen as a just response to aggression, meeting the criteria of just cause and legitimate authority. However, the involvement of NATO, Iran, North Korea, and China risks escalation, raising questions about proportionality and the potential for a wider war.
In the Middle East, Israel’s actions in Gaza, following Hamas’s October 2023 attack, have drawn scrutiny. The campaign, resulting in over 4,000 Palestinian deaths since March 2024, is defended by Israel as self-defence but criticised for violating proportionality and discrimination, with blockades on aid defying International Court of Justice orders. Iran’s support for Hamas and Hezbollah complicates the moral calculus, as its actions fuel regional instability while claiming to champion Palestinian rights.
Yemen’s civil war, with 150,000 deaths and 18 million facing food insecurity, sees the Houthis’ attacks on shipping justified as solidarity with Gaza, yet their actions disrupt global trade and invite retaliation. In Africa, conflicts in Sudan and the Democratic Republic of Congo, often under-reported, involve complex webs of state and non-state actors, making just war assessments murky.
China’s assertiveness over Taiwan, coupled with tensions in the South China Sea, poses another flashpoint. A potential Chinese invasion could trigger a U.S. response, risking a nuclear-armed conflict. Here, just war principles like last resort and reasonable success are overshadowed by strategic calculations and alliance obligations.
Mass immigration, driven by these conflicts, adds another layer. Over 110 million people are displaced globally, with 16 countries hosting over half a million refugees. This humanitarian crisis fuels political tensions, as seen in Trump’s militarisation of the U.S.-Mexico border, challenging the moral duty to protect vulnerable populations.
The Risk of World War: Is It Imminent?
The interconnectedness of today’s conflicts, Russia’s ties with Iran and North Korea, China’s economic support for Russia, and the Middle East’s cascading crises have led some, like analyst Fiona Hill, to argue that a third world war has already begun. The Global Peace Index notes 56 conflicts involving 92 nations, the highest since World War II, with 162,000 conflict-related deaths in 2023. The Doomsday Clock, set at 89 seconds to midnight, reflects unprecedented global peril.
Philosophers like Carl von Clausewitz viewed war as “politics by other means,” suggesting that escalation stems from unchecked power and ideological zeal. Putin’s autocratic ambitions, Iran’s regional revisionism, and China’s strategic patience over Taiwan echo this. Surveys show 61-64% of Western Europeans fear a global conflict within a decade, driven by distrust in institutions and rising militarisation.
Yet, some philosophers, like Jay Winter, caution against overstating parallels with 1914 or 1939, noting that nuclear weapons and global economic interdependence deter all-out war. Still, the erosion of the “rules-based order” and the failure of institutions like the UN to enforce peace raise the stakes.
Who Decides, and When?
Just war theory assigns decision-making to legitimate authorities, typically state leaders, but this assumes accountability and moral clarity. In democracies, public opinion and international law play roles, but autocrats like Putin or Xi face fewer checks, increasing the risk of miscalculation. The U.S., as a global hegemon, often acts unilaterally, as Obama noted in 2014, citing threats to allies or national interests. Yet, interventions like Iraq show how such decisions can falter without broad legitimacy.
International bodies like the UN Security Council are meant to arbitrate, but veto powers and geopolitical rivalries paralyse action. The International Court of Justice’s rulings, such as those on Gaza, are often ignored. Philosophers like Walzer argue that decisions to wage war must balance moral imperatives with pragmatic risks, but the threshold for “last resort” remains contentious when diplomacy fails, as in Ukraine or Yemen.
The Post-War World: A Glimpse Ahead
If a third world war erupts, its scale, potentially involving nuclear weapons, would dwarf past conflicts. The Atlantic Council’s 2025 foresight survey predicts a multipolar world with weakened multilateral institutions, where conflicts like Ukraine and Gaza fail to yield stable outcomes. A nuclear-armed Iran or a U.S.-China clash over Taiwan could reshape global power dynamics, with economic fallout triggering recessions.
Post-war, the world could face a “democratic depression,” with authoritarianism rising amid displaced populations and economic ruin. Yet, optimists suggest technological advances, like AI, could foster rebuilding, though 60% of experts see a bleaker future. The Middle East might see a reshuffled order, with Israel’s military dominance tempered by demands for Palestinian statehood. In Ukraine, a stalemate could solidify Russian gains, undermining sovereignty norms.
The Moral Precipice
Just war theory offers a framework to navigate the moral quagmire of conflict, but its application is fraught with ambiguity. Historical “just” wars, like World War II, show that moral clarity is rare and often comes at immense cost. Today’s crises, Ukraine, Gaza, Yemen, and beyond, highlight the fragility of ethical principles in a world of competing powers and failing institutions. While a third world war is not inevitable, the risk grows as diplomacy falters and revisionist states push boundaries. Philosophers urge restraint, proportionality, and accountability, but the question remains: can humanity heed these lessons before the next catastrophe? The answer lies in our collective will to prioritise peace over pride.