A good country does not begin a war except to defend its honor or to protect itself. ... Wars are unjust if they are undertaken without cause. Only a war waged in retaliation or defense can be considered just. ... No war is honorable unless it is announced and declared or it is for the recovery of property.

There is neither a foreign war nor a civil war; there is only just and unjust war.

When war is not just it is subsequently justified; so it becomes
many things. In reality, an unjust war is merely piracy.
It consists of piracy, ego and, more than anything, money.
War is our century's prostitution.

I am convinced that it is one of the most unjust wars that has ever been fought in the history of the world. Our involvement in the war in Vietnam has torn up the Geneva Accord. It has strengthened the military-industrial complex; it has strengthened the forces of reaction in our nation. It has put us against the self-determination of a vast majority of the Vietnamese people, and put us in the position of protecting a corrupt regime that is stacked against the poor.

There has never been a just [war], never an honorable one — on the part of the instigator of the war. I can see a million years ahead, and this rule will never change in so many as half a dozen instances. The loud little handful — as usual — will shout for the war. The pulpit will — warily and cautiously — object — at first; the great, big, dull bulk of the nation will rub its sleepy eyes and try to make out why there should be a war, and will say, earnestly and indignantly, 'It is unjust and dishonorable, and there is no necessity for it.' Then the handful will shout louder. A few fair men on the other side will argue and reason against the war with speech and pen, and at first will have a hearing and be applauded; but it will not last long; those others will outshout them, and presently the anti-war audiences will thin out and lose popularity. Before long you will see this curious thing: the speakers stoned from the platform, and free speech strangled by hordes of furious men who in their secret hearts are still at one with those stoned speakers — as earlier — but do not dare say so. And now the whole nation — pulpit and all — will take up the war-cry, and shout itself hoarse, and mob any honest man who ventures to open his mouth; and presently such mouths will cease to open. Next the statesmen will invent cheap lies, putting the blame upon the nation that is attacked, and every man will be glad of those conscience-soothing falsities, and will diligently study them, and refuse to examine any refutations of them; and thus he will by and by convince himself the war is just, and will thank God for the better sleep he enjoys after this process of grotesque self-deception.

An unavoidable war is called justice. When brutality is the only option left it is holy

Wars are never fought for altruistic reasons.

The only defensible war is a war of defense.

In a general view, there are few conquests that repay the charge of making them, and mankind are pretty well convinced that it can never be worth their while to go to war for profit's sake. If they are made war upon, their country invaded, or their existence at stake, it is their duty to defend and preserve themselves, but in every other light, and from every other cause, is war inglorious and detestable.

I am not a committed pacifist. I would not hold that it is under all imaginable circumstances wrong to use violence, even though use of violence is in some sense unjust. I believe that one has to estimate relative justices. But the use of violence and the creation of some degree of injustice can only be justified on the basis of the claim and the assessment-which always ought to be undertaken very, very seriously and with a good deal of scepticism that this violence is being exercised because a more just result is going to be achieved.

The Qur’an had begun to develop a primitive just war theory. In the steppes, aggressive warfare was praiseworthy; but in the Qur’an, self-defense was the only possible justification for hostilities and the preemptive strike was condemned.5 War was always a terrible evil, but it was sometimes necessary in order to preserve decent values, such as freedom of worship. Even here, the Qur’an did not abandon its pluralism: synagogues and churches as well as mosques should be protected. The Muslims felt that they had suffered a fearful assault; their expulsion from Mecca was an act that had no justification. Exile from the tribe violated the deepest sanction of Arabia; it had attacked the core of the Muslims’ identity.

There is no greater guilt than the unneccessary war.

Неизбежните войни са винаги справедливи войни.

No. There is one fairly good reason for fighting — and that is, if the other man starts it. You see, wars are a wickedness, perhaps the greatest wickedness of a wicked species. They are so wicked that they must not be allowed. When you can be perfectly certain that the other man started them, then is time when you might have a sort of duty to stop him.