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 are only two cases in which war is just: first, in order to resist the aggression of an enemy, and second, in order to help an ally who has been attacked.

All interstate wars intensify aggression – maximize it … some wars are even more unjust than others. In other words, all government wars are unjust, although some governments have less unjust claims…

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

The just war theory says you need a legitimate authority to declare and to wage war. Only the United Nations is that legitimate authority. Any other war is immoral. The just war says, “Have you exhausted all possible peaceful means?” And the world says, “No, we haven’t yet!” And any war before you have exhausted all possible peaceful means is immoral. And those who want to wage war against Iraq must know it would be an immoral war.

The term "just war" contains an internal contradiction. War is inherently unjust, and the great challenge of our time is how to deal with evil, tyranny, and oppression without killing huge numbers of people.

Iraq is an unjust war. I thought then, and I think now, that the invasion of Iraq was unnecessary and unjust. And I think the premises on which it was launched were false.

4374. That War only is just, which is necessary.

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.

History shows that wars are divided into two kinds, just and unjust. All wars that are progressive are just, and all wars that impede progress are unjust. We Communists oppose all unjust wars that impede progress, but we do not oppose progressive, just wars. Not only do we Communists not oppose just wars; we actively participate in them. As for unjust wars, World War I is an instance in which both sides fought for imperialist interests; therefore, the Communists of the whole world firmly opposed that war. The way to oppose a war of this kind is to do everything possible to prevent it before it breaks out and, once it breaks out, to oppose war with war, to oppose unjust war with just war, whenever possible.

As to war, I am and always was a great enemy, at the same time a warrior the greater part of my life, and were I young again, should still be a warrior while ever this country should be invaded and I lived — a Defensive war I think a righteous war to Defend my life & property & that of my family, in my own opinion, is right & justifiable in the sight of God. An offensive war, I believe to be wrong and would therefore have nothing to do with it, having no right to meddle with another man's property, his ox or his ass, his man servant or his maid servant or anything that is his. Neither does he have a right to meddle with anything that is mine, if he does I have a right to defend it by force.

No wars are unintended or 'accidental'. What is often unintended is the length and bloodiness of the war.

The only war worse than one that’s intended is one that’s unintended.

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.