The questions of morality arising out of these things are many and complicated, and they cannot be disposed of by short and simple formulæ. How far is a statesman who sees, or thinks he sees, some crushing danger from an aggressive foreign Power impending over his country, justified in anticipating that danger, and at a convenient moment and without any immediate provocation forcing on a war? How far is it his right or his duty to sacrifice the lives of his people through humanitarian motives, for the redress of some flagrant wrong with which he is under no treaty obligation to interfere? How far, if several Powers agree to guarantee the integrity of a small Power, is one Power bound at great risk to interfere in isolation if its co-partners refuse to do so or are even accomplices in a policy of plunder? How far, if the aggression of other Powers places his nation at a commercial or other disadvantage in the competition of nations, may a statesman take measures which, under other circumstances, would be plainly unjustifiable, to guard against such disadvantage? With what degrees of punctiliousness, at what cost of treasure and of life, ought a nation to resent insults directed against its dignity, its subjects and its flag? What is the meaning and what are the limits of national egotism and national unselfishness? There is such a thing as the comity of nations, and even apart from treaty obligations no great nation can pursue a policy of complete isolation, disregarding crimes and aggressions beyond its border. On the other hand, the primary duty of every statesman is to his own country. His task is to secure for many millions of the human race the highest possible amount of peace and prosperity, and a selfishness is at least not a narrow one which, while abstaining from injuring others, restricts itself to promoting the happiness of a vast section of the human race. Sacrifices and dangers which a good man would think it his clear duty to accept if they fell on himself alone wear another aspect if he is acting as trustee for a great nation and for the interests of generations who are yet unborn. Nothing is more calamitous than the divorce of politics from morals, but in practical politics public and private morals will never absolutely correspond. The public opinion of the nation will inevitably inspire and control its statesmen. It creates in all countries an ethical code which with greater or less perfection marks out for them the path of duty, and though a great statesman may do something to raise its level, he can never wholly escape its influence. In different nations it is higher or lower--in truthfulness and sincerity of diplomacy the variations are very great--but it will never be the exact code on which men act in private life. It is certainly widely different from the Sermon on the Mount.