In the sixteenth year of the Peloponnesian War, an Athenian expedition descended upon the small island of Melos, about 90 miles south of Athens in the Aegean Sea, and demanded that the Melians join in alliance or be destroyed. Although a Spartan colony, Melos had remained scrupulously neutral in the war. Her citizens, unwilling to renounce their independence, sought unsuccessfully to dissuade the Athenians from attacking them. The Athenians explained that an independent Melos situated in the very heart of the Athenian imperium encouraged other island allies to aspire toward independence. Their failure to put an end to the anomaly of Melian independence would therefore be seen by friend and foe alike as a sign of weakness on Athens' part.

The really intriguing question about the Melian dialogue is not the Athenian decision to invade Melos but rather Athenian toleration of Melian independence for the first sixteen years of the Peloponnesian War. For surely, if Melian independence constituted a threat to Athens in 416 B.C. it must have done so in 430 B.C., the year in which the war broke out, and in all of the years in between. Why then did Athens wait so long to impose its hegemony over the island? The answer, implicit in Thucydides' narrative history of the Peloponnesian War, contains an important insight into the nature of aggression, one, moreover, that is particularly germane to contemporary international relations.

The Athenian reply to the Melians stresses the subjective nature of power; if others think of you as powerful, you are powerful and vice versa. For this reason, states must be concerned about their image abroad and must from time to time offer vivid demonstrations of their capability and resolve. The Athenian invasion of Melos, unnecessary for any strategic reason, was envisaged as such a display.

The strategic consensus that has characterized American official and popular thinking about nuclear weapons since World War II has greatly eroded in recent years. That consensus consisted not only of an American determination to use nuclear weapons to deter a direct Soviet attack on the United States but also of a commitment to extend the American deterrent to cover a Soviet nuclear or large-scale conventional attack on America's principal allies. In the face of the recent massive and continuing growth of Soviet nuclear and conventional capabilities this consensus has come under growing challenge.

This challenge to the consensus on the policy of nuclear deterrence has come from both ends of the political spectrum. On the political “right,” the Reagan administration has argued that deterrence alone is too weak a reed to forestall a Soviet attack on the United States or one of its allies; the prevention of a Soviet attack requires the development of a nuclear war-fighting strategy similar to that which the Soviets themselves are presumed to possess. On the political “left,” a large and highly vocal antinuclear movement largely under the banner of the “freeze,” challenges one aspect or another of the deterrence strategy and demands a deemphasis on, if not the complete elimination of, nuclear weapons. Both of these positions, I believe, are flawed and fail to provide a satisfactory solution to the difficult situation in which the United States finds itself in the closing decades of the twentieth century.

Of all modern machines, indeed of all the artifacts of modern culture, the bomb is the most frightening. It is the most dangerous of all human inventions. The American, European, and Soviet people have always known how dangerous it is. They have, nevertheless, left nuclear weapons in the hands of the nuclear priesthood. (In the Soviet Union this has not been a matter of choice.) In the 1980s some in the West resolved to take control of the bomb. They began to demand that disarmament replace deterrence as the principal nuclear business of the Atlantic alliance.

Probably from 1945 onward the average American or European would, if asked, have said that he wanted to do away with all nuclear arsenals rather than refine or increase them. But the average Westerner was not asked, and did not say so, at least not in any way that influenced public policy. In the 1980s citizens of the West did begin to say so, publicly, loudly, and in growing numbers. For the first time, a mass movement dedicated to shaping the nuclear future appeared on both sides of the Atlantic.

In this, as in other things, the North American and the European wings of NATO differ. Opposition to the alliance's nuclear weapons policies made itself known earlier in Europe than in the United States. Both European and American anti-nuclear weapons activists aimed ultimately to lift the nuclear siege that the world must endure as long as these weapons exist. But each rallied around a more immediate issue, and the issues were different. The Europeans opposed the stationing of 572 intermediate-range missiles on the continent, which the NATO governments deemed necessary to offset comparable Soviet weapons. In the United States a proposal to freeze the deployment, testing, and manufacture of all weapons by both superpowers attracted wide support.

A rational strategy for the employment of nuclear weapons is a contradiction in terms. The enormity of the destruction, either executed or threatened, severs the nexus of proportionality between means and ends which used to characterize the threat and use of force. This does not mean, however, that all nuclear strategies are equally irrational. The nuclear policy of the Reagan administration—which is essentially the same as that of the Carter administration and which has its roots in developments initiated by even earlier administrations—is particularly ill-formed. As I will demonstrate, the basic reason for this is that the strategy rests on a profound underestimation of the impact of nuclear weapons on military strategy and attempts to understand the current situation with intellectual tools appropriate only in the pre-nuclear era.

American strategy for the past several years—the “countervailing strategy”—has been based on the assumption that what is crucial is the ability of American and allied military forces to deny the Soviets military advantage from any aggression they might contemplate. The U.S. must be prepared to meet and block any level of Soviet force. The strategy is then one of counterforce—blocking and seeking to destroy Soviet military power. The goal is deterrence. Although it is concerned with how the U.S. would fight many different kinds of wars, both nuclear and non-nuclear, it is not correct to claim that the strategy seeks to engage in wars rather than deter them.