Montesquieu (1689–1755). Persian Letters. 1901.
Letter XCVIUsbek to the Same
M
There is rarely need for a third party to act as umpire between nation and nation, because the subjects in dispute are almost always clearly defined and easily decided. The interests of two nations are usually so distinct, that it is only necessary to love justice to discover where it lies; one can hardly be prejudiced in one’s own cause.
It is not the same with the differences which happen among individuals. As they live together, their interests are so intermingled and so confused, and also so various, that it is necessary for a third party to clear that which the covetousness of the other two endeavors to obscure.
There are only two kinds of just wars: those which are waged to repel an attacking enemy, or to aid an ally who is attacked.
There would be no justice in making war for the private quarrels of a prince, unless the crime were so grave as to require the death of the prince or of the people who committed it. Thus, a prince ought not to make war because he has been refused an honor which is his due, or because his ambassadors have been treated with scant courtesy, or for any such reason; any more than a private person should kill him who refuses him precedence. The reason of this is, that, since a declaration of war ought to be an act of justice, which always requires the punishment to be proportioned to the crime, it is necessary to make sure that he upon whom war is declared merits death: for to wage war on any one is to pronounce against him the death penalty.
In international law the severest act of justice is war, since it may have the effect of destroying society.
Reprisals are next in severity. No tribunal has been able to avoid the law which proportions the punishment to the crime.
A third act of justice is to deprive a prince of the advantages which he may derive from us, always measuring the penalty by the offense.
The fourth act of justice, which ought to be the most frequent, is to renounce the alliance of a people which gives cause of complaint. This penalty corresponds to that of banishment, which has been established by tribunals to remove criminals from the community. In this way, the prince whose alliance we renounce is cut off from our community, and is no longer one of the members which compose it.
No greater insult can be offered a prince, than to renounce his alliance, and no greater honor can be conferred upon him, than to enter into one with him. Nothing on earth adds more to our honor, and is really more useful, than to see others always careful of our preservation.
But, in order that the alliance may be binding, it must be just: thus an alliance contracted between two nations to oppress a third is not lawful; and there would be no guilt in breaking it.
It is by no means honorable or dignified in a prince to ally himself with a tyrant. They say that an Egyptian monarch once remonstrated with the king of Samos upon his cruelty and tyranny, and called upon him for amendment; and when he would not amend, he sent to him renouncing his friendship and alliance.
Conquest in itself does not establish a right. As long as a community holds together, it is a pledge of peace, and of the reparation of wrong; if it is destroyed or dispersed, it is a monument of tyranny.
Treaties of peace are so sacred among men, that they seem to be the voice of nature reclaiming her rights. They are quite legitimate, when the conditions are such that both nations can preserve themselves; without that, the nation which would perish, deprived of its natural defense by peace, may seek safety in war.
For nature, although she has fixed different degrees of strength and weakness among men, has often by means of despair made the weak equal to the strong.
This, my dear Rhedi, is what I call international law, the law of peoples, or rather, the law of right.
P