The concept of a "just war" is at least a logical one; that is, it is logically possible that there is a war which is carried out for just and humane ends. More precisely, there may be an intersection of the facts of justice and war, it not necessarily being an empty set. To look at it in this perspective means that we must consider the question, what is an unjust war, as well; to say nothing of the questions of a just peace or an unjust peace, which however are not the subject of this essay.

The fact that a war may be just does not thereby mean that it is also "good", that is, an undivided blessing for all the people involved. If even one person dies durlng a war, it can be said that the war is at least bad for that person, particularly if they are not directly involved in it. On the other hand, it may be that death is not the greatest evil, and that it may be the better part for a person to live his life towards some greater end, that is, in the service of justice. So we cannot judge the justice of a war by the individual harms which may be suffered because of that war, as much as we would like to believe that all suffering is unjust.

To clearly answer these questions, what is a just war and what is an unjust war, we must be clear on what is justice; it is quite clear what war is. If an alien race from another planet landed, and attempted to enslave and torture all humankind, we might consider it our right, and hence justified and therefore just to resist even with violence in order to protect ourselves and drive away the invaders. Conversely if any invasion of our lives is justifiably resisted then all wars may be just ones. But so far we have not clarified the meaning of justice, particularly in the context of war.

Let us try to be very specific about what justice is. Justice happens, or is carried out, whenever the participants in a dispute receive what is their due. On the simplest level, what is just is equivalent to what is fair; if we are arguing about the meaning of a word, it is only fair that you listen to my opinion; if we are attempting to divide something, whether a piece of cake or a piece of property, fairness requires that we each receive a due proportion, although they may not be equal. On another level of human interactions where the disputants cannot settle the matter themselves equitably, we have courts and laws and trials and judges all of which are constructed in an attempt to insure that each person receives what is due them, both in process and in recompense or division of property. If this in fact be the meaning of justice, then on the level of interaction of states justice means that each state would receive what is due that state. When we get down to cases we find that, as on the other levels as well for each party to end up with what is due them may mean taking from one and giving to another, with the result that an inequity may be perceived from the side of the one taken from, regardless of the previous history. That is, for example, the restoration of the Polish nation after one hundred and fifty years may be regarded as a "just" event from the point of view of the Polish people, and I am not arguing against it, but it may similarly be regarded as unjust from the point of view of the surrounding nations whose territory was taken from them. The point is, that the current situation may be regarded as the "just" one, or it may be decided that it is more equitable to take from one and give to another.

However, it is questionable whether all parties in a dispute can receive what is their due i.e., obtain a just result, through the means of war and battle. For in wars and battles it is necessarily the strongest disputant who must win and therefore the distribution of the matter under argument can hardly be said to be equitably carried out; the losers can hardly be said to have received their due if the victors determine what that is. Therefore it would appear that no war can be a just war.

This is not to say whether any war can be advisable however, or even successful. Especially in the case of defensive battles against invaders, to fight may be the simplest and most obvious way to preserve one's existence, both personal and societal. But even a defensive victory may end up a moral loss, however since it will tend to persuade the victors that battle is profitable and lead them into aggressive wars and cause them to become invaders themselves.