"Realism maintains that universal moral principles cannot be applied to the actions of states in their abstract universal formulation, but that they must be filtered through the concrete circumstances of time and place. The individual may say for himself: "Fiat justitia, pereat mundus ," but the state has no right to say so in the name of those who are in its care. Both individual and state must judge political action by universal moral principles, such as that of liberty. Yet while the individual has a moral right to sacrifice himself in defense of such a moral principle, the state has no right to let its moral disapprobation of the infringement of liberty get in the way of successful political action, itself inspired by the moral principle of national survival."

“When we speak of power, we mean man's control over the minds and actions of other men. By political power we refer to the mutual relations of control among the holders of public authority and between the latter and the people at large.”

“Throughout the nation's history, the national destiny of the United States has been understood in antimilitaristic, libertarian terms.”

“Political realism is aware of the moral significance of political action. It is also aware of the ineluctable tension between the moral command and the requirements of successful political action. And it is unwilling to gloss over and obliterate that tension and thus to obfuscate both the moral and the political issue by making it appear as though the stark facts of politics were morally more satisfying than they actually are, and the moral law less exacting than it actually is.”

“The struggle for power is universal in time and space and is an undeniable fact of experience. It cannot be denied that throughout historic time, regardless of social, economic and political conditions, states have met each other in contests for power. Even though anthropologists have shown that certain primitive peoples seem to be free from the desire for power, nobody has yet shown how their state of mind can be re-created on a worldwide scale so as to eliminate the struggle for power from the international scene. … International politics, like all politics, is a struggle for power. Whatever the ultimate aims of international politics, power is always the immediate aim.”

“Political realism refuses to identify the moral aspirations of a particular nation with the moral laws that govern the universe. As it distinguishes between truth and opinion, so it distinguishes between truth and idolatry. All nations are tempted — and few have been able to resist the power for long — to clothe their own aspirations and action in the moral purposes of the universe. To know that nations are subject to the moral law is one thing, while to pretend to know with certainty what is good and evil in the relations among nations is quite another. There is a world of difference between the belief that all nations stand under the judgment of God, inscrutable to the human mind, and the blasphemous conviction that God is always on one's side and that what one wills oneself cannot fail to be willed by God also.”