Influence can persuade, but power can compel. - Hans Morgenthau

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.

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.

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