Is There Such a Thing as a “Just War”?

Photograph by Nathaniel St. Clair

War is a man-made catastrophe that is almost always preventable, but prevention fails because of poor diplomacy, bad faith, intransigence, or an animus dominandi bent on aggression.  Once unleashed war becomes unpredictable and often yields other results than those intended.

Confidence building among nations is the best prevention against war, the availability of forums to facilitate dialogue and compromise.  Retrospectively, it is easy to see where mistakes were made and how the outbreak of war could have been avoided.  But very few politicians have ever learned from the mistakes of prior wars, few have learned anything at all from history. They live in their own worlds and believe their own propaganda.

What we know of history is mostly a form of literature akin to politicized fiction.  Histories are written to legitimize the authority of the powerful, to justify the result of the wars and apportion blame as necessary for the desired political narrative.  The ideal of history-writing proposed by the 19th-century German historian Leopold von Ranke, according to whom a historian should “simply” write history “wie es eigentlich gewesen” – how it actually happened – is not that simple, and has never been achieved.

Personally, I would propose seven C’s of history-writing:  chronology, context, comprehensiveness, coherence, causality, comparison, and last but not least, cui bono (Cicero, Pro Milone, who benefits?).  The best approach to history is not to take it as dogma or divine revelation, but as a partial description of events that have occurred. The narrative that joins the dots and collects the facts into a half-way coherent story, reflects the a prioris of the writer and the necessity to summarize and condense, since the mass of information is overwhelming.

Writing history entails selecting facts and ordering them in a coherent way.  Objectivity is desirable, but seldom achieved.  The worst histories are those that pretend to explain “the origins of the war” e.g. the Peloponnesian war, the first and second world wars, etc. because the historian is not writing in a vacuum or for future generations, but for his/her generation that wants to believe certain things and at the same time forget others.  Already Julius Caesar noted in his De bello civile (2,27,2)“quae volumus ea credimus libenter”, we tend to believe what we want to believe.

War histories can be fascinating to read, but it is advisable to receive them cum grano salis – with a grain of salt. It is best to rely on multiple sources, not just the histories written by the victors, but also the unwritten histories in the archives or the memoirs of the vanquished political and military leaders.  Indeed, it is most revealing to read the memoirs of Confederate General Robert E. Lee[1], or German Field Marshall Erich von Manstein’s Verlorene Siege [2].

In order to prevent war, it is appropriate to rely on mediation by neutral third parties.  Recently the importance of having neutral States has been disregarded and the tendency has been to divide the world in Manichaean fashion into good and bad states and forcing formerly neutral States like Switzerland to choose camps.  This is an ominous development, bearing in mind that Switzerland has in the past facilitated high-level meetings between rivals.

The tools of diplomacy are there, but most of all what is needed is good faith and the readiness to consider compromise and quid pro quo.  When we think of recent wars and other instances of armed conflict, we realize that often the parties were rigid and intransigent, lacking a mindset conducive to compromise.  History also shows that we have what I would call a tradition of cheating, a culture of lying to the other party[3].  This augurs badly for any agreement that could be sustainable.

Apologia for war

There is no excuse for war, but there are plenty of apologists.[4] For millennia those who hold power have aspired to greater power. We humans are predators and aggression has been part of human history.  Military “virtues” are hailed and patriotism[5] is frequently defined in connection with war. In history class, we are taught to honor the memory of war heroes.  Glory is somehow associated more with war than with great achievements in medicine, music or literature.

Religion has also played a role in justifying aggression.  Many civilizations have had a “God of War”, whether we call him Mars or Dominus Deus Sabaoth (Ἅγιος, ἅγιος, ἅγιος Κύριος Σαβαώθ), Lord of the Armies.  Priests have blessed cannons and guns, tsarist Russian armies went to war under the motto “God with us” Съ нами Богъ!, similarly Nazi Germany “Gott mit uns”.  The appeal to God lends credence to the official propaganda that we are the “good guys” and that our enemies are necessarily the “bad guys”. Sometimes similar words have been inscribed on bombs.  The level of superstition – and blasphemy – is considerable. In any event, the appeal to God is tantamount to saying that ours is the only just cause and thus we have the right to wage the “good war.”

The Just War Theory

There is, of course, an old debate about what a “just war” (bellum justum) is supposed to be. Here we must make a distinction between going to war (jus ad bellum) and the laws of warfare (ius in bello) laid down in the Hague and Geneva Conventions.

In many cases, there is an aggressor and a victim, but this is not always the case, since the complexities of international relations spread the blame among many players.  Surely it is simplistic to claim that the only guilty party is the one who fires the first bullet, notwithstanding menaces and provocations[6]that may have preceded that first bullet. There are wars in which all parties are guilty of egregious “injustice” and have no moral right to claim any ethical superiority over the others.  And even a “victim” of aggression may, by grossly violating the ius in bello render what could have been a “just” self-defense into serial war crimes and crimes against humanity.

For millennia going to war has been the prerogative of kings and heads of state.  It was considered an attribute of every sovereign state and practiced worldwide in the sense of Carl von Clausewitz’s statement: “War is a continuation of politics by other means.”[7] Since time immemorial, conquest has been a practice that has been endured by millions of human beings and has been recorded by historians, sometimes adorned with a flattering splashing of glory.  Alexander the Great, Julius Caesar, Attila the Hun, Genghis Khan, Tamerlane, Louis XIV, Napoleon, President Andrew Jackson, Queen Victoria, Leopold II of Belgium[8], Theodore Roosevelt[9], Hitler have all engaged in wars of conquest costing millions of human lives. The number of outrageously unjust wars is endless, from the Roman conquests of Gaul to the US wars against the First Nations of North America[10], to the Opium Wars against China[11] to the US overthrow of the Hawaiian Kingdom and its subsequent annexation through a fraudulent referendum[12], to the Spanish-American war of 1898.

Since the entry into force of the UN Charter on 24 October 1945 the use of force is prohibited by virtue of article 2(4) of the Charter and permitted only with express consent by the Security Council or – only temporarily – pursuant to article 51 of the Charter, which stipulates the right of self-defense, provided that a previous attack has occurred.  The so-called doctrine of “Responsibility to Protect” (R2P)[13] is a dangerous invention, devised to pretend that a foreign military intervention can be somehow legitimized by reference to “humanitarian principles”, which are not defined and can be invoked à la carte.  Luckily, R2P is only “soft law” and cannot derogate from the obligation to refrain from the use of force without UN approval.  It bears repeating that in case of conflict between the UN Charter and any other treaty, including the Treaty of the North Atlantic Treaty Organization, it is the UN Charter that prevails pursuant to the “supremacy clause” laid down in Article 103 of the Charter.


Revisiting the old theory of the “just war”, we recognize a moral element, an effort to assert a kind of military ethics, which should ensure that an armed conflict is morally justifiable. According to the “theory”, which this author rejects, there are four criteria to be satisfied for a war to be considered “just”.

From the classical writings of Christian theologians, including St. Augustine[14] and St. Thomas Aquinas[15], a just war requires that 1) the war be declared by competent authority, 2) probability of success, e.g. a war must not be a risky va banque speculation; the aims of the just war must be reasonably achievable with the least amount of force, 3) war can only be a last resort, after all non-violent options have been exhausted, and 4) there must be a just cause, a legitimate casus belli, e.g. the necessity to stop genocide, but not simply trying to recapture lost territories[16], teaching the “enemy” a lesson or collectively punishing peoples.

While an aggression automatically delegitimizes any argument of a “just war”, it must also be borne in mind that aggression frequently has a pre-history, and the target of the aggression may itself bear considerable responsibility for the outbreak of hostilities.  Indeed, if a State engages in provocation and sabre-rattling, if a State deliberately escalates tensions and gives reason to another State to feel existentially threatened, then the provoker may actually bear greater responsibility than the State that has been driven to a kind of “pre-emptive self-defense”.  Admittedly, article 51 of the UN Charter does not allow any kind of pre-emptive self-defense, but at the same time it must be borne in mind that by provoking another state, the provoker is violating article 2(4) of the UN Charter, which specifically prohibits the threat of the use of force.

Undoubtedly, insurrection against oppressive rule is morally legitimate. Already the French Enlightenment philosopher Jean-Jacques Rousseau argued this, and the US Declaration of Independence of 4 July 1776 reads in part “That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it… it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.”  This is an eloquent expression of the right of self-determination of peoples, in particular the right to resist oppression.[17]

This idea has been incorporated into numerous UN General Assembly Resolutions, including the 1974 Declaration on Aggression[18], article 7 of which stipulates:

“Nothing in this Definition, and in particular article 3, could in any way prejudice the right to self-determination, freedom and independence, as derived from the Charter, of peoples forcibly deprived of that right and referred to in the Declaration on Principles of International Law concerning Friendly Relations and Cooperation among States in accordance with the Charter of the United Nations, particularly peoples under colonial and racist regimes or other forms of alien domination: nor the right of these peoples to struggle to that end and to seek and receive support, in accordance with the principles of the Charter and in conformity with the above-mentioned Declaration.”[19]

Alas, the right of self-determination of peoples, anchored in the UN Charter (articles 1, 55, Chapter XI, XII) and in article 1 common to the International Covenant on Civil and Political Rights and the International Covenant on Economic Social and Cultural rights, is not self-executing.  Many peoples with legitimate aspirations to self-determination have rebelled against oppression and been massacred in the process, including the Igbos and Ogonis of Biafra and the Tamils of Sri Lanka[20]. While their insurrection could be considered a “just war”, their inability to succeed has further reduced the validity of the “just war” theory, since the world watched and did nothing to prevent the massacres.

Another consideration of a “just war” is that in the conduct of the armed conflict, the two principles of international humanitarian law be respected.  The principle of distinction between combatants and non-combatants, between military and civilian targets, and the principle of proportionality.  It is clear that Israel has violated both principles in its long history of attacks against the Palestinians in the Occupied Territories and in Gaza.

A wider understanding of a “just war” would necessarily encompass the ethics and viability of post-war settlements – a jus post-bellum.  While the general idea is that all wars must be prevented and that the United Nations should be more proactive in mediating peace, it is most important to ensure that post-war arrangements provide for conditions of sustainable peace.  In this context, it is far more important to provide immediate humanitarian assistance to victims on all sides of a conflict and take measures aimed a reducing hatred with a view to reconciliation and reconstruction.  In particular, the text of Article 20 of the International Covenant on Civil and Political Rights must be kept in mind – the prohibition of war propaganda and incitement to hatred and violence.  Indeed, most wars have been sustained by propaganda and hate-mongering.  What is necessary is to implement the promise of the UNESCO Constitution that “since wars begin in the minds of men, it is in the minds of men that the defences of peace must be constructed.”[21] 


All wars are unjust. They outrage the humanity of civilians and soldiers alike. The material and spiritual damage caused is colossal, leaving wounds that can only heal with time and caritas.

Lawyers, historians and the media all collude in concocting the apologetics of war and presenting multiple murders in the noble light of defending vital interests, “self-sacrifice”, patriotism, and elevating warfare on the pedestal of national pride and fountainhead of the “glory” of the nation. Indeed, all wars unleash good and bad human traits.  There is true heroism and genuine self-sacrifice, which deserve our respect.  But heroism is not the exclusive domain of one party to a conflict.  There are heroes on all sides.  Alas, their courage and sacrifice are wasted.

No, there are no “just wars” but only slaughter.  The so-called “just war doctrine” is an obsolete scam (abolished by the UN Charter) to justify aggression and land grabs.  The only “just war” is a war we must wage against the arrogance of power[22], against the mentality that considers provocations and sabre-rattling as a kind of “sport”, although this kind of arrogance almost always leads to armed conflict.

The Roman poet Horatius painted war in pastel colors, “dulce et decorum est pro patria mori” – it is sweet and proper to die for the homeland – but why not LIVE for the homeland, for one’s family, children and grandchildren, for future generations, for beauty, music, the common heritage of mankind? War is neither just nor noble.  It is obscene.








[7] “Der Krieg ist eine bloße Fortsetzung der Politik mit anderen Mitteln.” – Vom Kriege, 1. Buch, 1.

[8] Matthew Stanard, Matthew G. Selling the Congo: A history of European pro-empire propaganda and the making of Belgian imperialism, University of Nebraska Press, Lincoln, 2012.

[9] Gregg Jones, Honor in the Dust: Theodore Roosevelt, War in the Philippines,. New American Library, 2013.

[10] David Stannard, American Holocaust, Oxford University Press. 1992.



[13] General Assembly Resolution 60/1 of 24 October 2005, paragraphs 138-39.

[14] City of God, Political and Social Philosophy “War and Peace – the Just War”; Thornton Lockwood, Cicero’s Philosophy of Just War, taken from a missing fragment of Cicero’s dialogue On the Republic.

[15] Summa Theologica, Christian Classics Ethereal Library. pp. pt. II, sec. 2.

[16] This means inter alia that it would not be a “just war” if  the Germans were to start a war to recapture their 700 year-old homelands in East Prussia, Pomerania, Silesia and East Brandenburg, lost to Poland at the end of World War II, nor Azerbaijan carry out a Blitzkrieg to recapture the Armenian territories of Nagorno Karabakh, nor Ukraine the Russian-populated territories of Crimea and Donbas.






[22] J. William Fulbright, The Arrogance of Power, Random House New York 1966.

Alfred de Zayas is a law professor at the Geneva School of Diplomacy and served as a UN Independent Expert on International Order 2012-18. He is the author of twelve books including “Building a Just World Order” (2021) “Countering Mainstream Narratives” 2022, and “The Human Rights Industry” (Clarity Press, 2021).