Because moralists in these matters are always driven by righteous passion, whenever you disagree with them, you are by definition immoral and deserve no quarter; whereas realists, precisely because they are used to conflict, are less likely to overreact to it. Realists know that passion and wise policy rarely flow together. (The late diplomat Richard Holbrooke was a stunning exception to this rule.) Realists adhere to the belief of the mid-twentieth-century University of Chicago political scientist, Hans Morgenthau, who wrote that “one must work with” the base forces of human nature, “not against them.” Thus, realists accept the human material at hand in any given place, however imperfect that material may be. To wit, you can’t go around toppling regimes just because you don’t like them. Realism, adds Morgenthau, “appeals to historical precedent rather than to abstract principles [of justice] and aims at the realization of the lesser evil rather than of the absolute good.”

No group of people internalized such tragic realizations better than Republican presidents during the Cold War. Dwight Eisenhower, Richard Nixon, Ronald Reagan and George H. W. Bush all practiced amorality, realism, restraint and humility in foreign affairs (if not all the time). It is their sensibility that should guide us now. Eisenhower represented a pragmatic compromise within the Republican Party between isolationists and rabid anti-Communists. All of these men supported repressive, undemocratic regimes in the third world in support of a favorable balance of power against the Soviet Union. Nixon accepted the altogether brutal regimes in the Soviet Union and “Red” China as legitimate, even as he balanced one against the other. Reagan spoke the Wilsonian language of moral rearmament, even as he awarded the key levers of bureaucratic power to realists like Caspar Weinberger, George Shultz and Frank Carlucci, whose effect regarding policy was to temper Reagan’s rhetoric. The elder Bush did not break relations with China after the Tiananmen uprising; nor did he immediately pledge support for Lithuania, after that brave little country declared its independence—for fear of antagonizing the Soviet military. It was caution and restraint on Bush’s part that helped bring the Cold War to a largely peaceful—and, therefore, moral—conclusion. In some of these policies, the difference between amorality and morality was, to paraphrase Joseph Conrad in Lord Jim, no more than “the thickness of a sheet of paper.”

And that is precisely the point: foreign policy at its best is subtle, innovative, contradictory, and truly bold only on occasion, aware as its most disciplined practitioners are of the limits of American power. That is heartrending, simply because calls to alleviate suffering will in too many instances go unanswered. For the essence of tragedy is not the triumph of evil over good, so much as the triumph of one good over another that causes suffering.