No war ought ever to be undertaken but under circumstances which render all intercourse of courtesy between the combatants impossible. It is a bad thing that men should hate each other; but it is far worse that they should contract the habit of cutting one another's throats without hatred. War is never lenient but where it is wanton; when men are compelled to fight in self-defence, they must hate and avenge: this may be bad; but it is human nature.