It is my strong conviction that a realist conception of human nature should be made a servant of an ethic of progressive justice and should not be made into a bastion of conservatism, particularly a conservatism which defends unjust privileges.
Reinhold NiebuhrOur dreams of bringing the whole of human history under the control of the human will are ironically refuted by the fact that no group of idealists can easily move the pattern of history toward the desired goal of peace and justice. The recalcitrant forces in the historical drama have a power and persistence beyond our reckoning.
Reinhold NiebuhrDemocracies are indeed slow to make war, but once embarked upon a martial venture are equally slow to make peace and reluctant to make a tolerable, rather than a vindictive, peace.
Reinhold Niebuhr