It is usually said, first, that the different powers, who go to war, give it out that their wars are defensive, or that they justify themselves on this principle.
I shall observe in reply to this, that it is frequently difficult to determine, where actual aggression begins. Even old aggressions, of long standing, have their bearings in these disputes. Not shall we find often any clue to a solution of the difficulty in the manifestoes of either party, for each makes his own case good in these; and if we were to decide on the merits of the question by the contents of these, we should often come to the conclusion, that both the parties were wrong. Thus, for instance, a notion may have been guilty of an offence to another. So far the cause of the other is a just one. But if the other should arm first, and this during an attempt at accommodation, it will be a question, whether it does not forfeit its pretensions to a just case, and whether both are not then to be considered as aggressors on the occasion?
When a nation avows its object in a war, and changes its object in the course of it, the presumption is, that such a nation has been the aggressor. And where any nation goes to war upon no other avowed principle, than that of the balance of power, such a nation, however right according to the policy of the world, is an aggressor according to the policy of the Gospel, because it proceeds upon the principle, that it is lawful to do evil, that good may come.
If a nation hires or employs the troops of another to fight for it, though it is not the aggressor in any war, yet it has the crime upon its head of making those aggressors, whom it employs.
But, generally speaking, few modern wars can be called defensive. A war, purely defensive, is that in which the inhabitants of a nation remain wholly at home to repel the attacks of another, and content themselves with sending protection to the settlements which belong to it. But few instance are recorded of such wars.
But if there be often a difficulty in discerning between aggressive and defensive wars, and if, moreover, there is reason to suppose, that most of the modern wars are aggressive, or that both patties become aggressors in the course of the dispute, it becomes the rulers of nations to pause, and to examine their own consciences with fear and trembling, before they allow the Sword to bedrawn, lest a dreadful responsibility should fall upon their heads for all the destruction of happiness, all the havoc of life, and all the slaughter of morals that may ensue.
It is said, secondly, that if any nation were publicly to determine to relinquish the practice if war, or to act on the policy of the Gospel, it would be overrun by other nations which might act on the policy of the world.
This argument is neither more nor less than that of the Pagan Celsus, who said in the second century, that, if the rest of the Roman empire were Christians, it would be overrun by the Barbarians.
Independently of the protection, which such a nation might count upon from the moral Governor of the world, let us enquire, upon rational principles, what would be likely to be its fate.
Armies, we know, are kept up by one nation, principally because they are kept up by another.