The nuclear age began in mid-July 1945 when an 18.6-kiloton nuclear bomb was detonated at the Trinity test site near Alamogordo, New Mexico. Three weeks later, on 6 August 1945, the world became aware of the existence of nuclear weapons when a U.S. B-29 bomber known as Enola Gay dropped a nuclear bomb on the Japanese city of Hiroshima. That was followed three days later by the dropping of another bomb on Nagasaki. The term nuclear age was coined almost immediately after the two bombs were used. Within days of the Nagasaki bombing, the publisher Pocket Books put out a special primer titled The Atomic Age Opens, edited by Gerald Wendt. The phrase atomic age remained more common than nuclear age through the mid-1950s, but nuclear age already enjoyed wide use in 1945. By the end of the year, it had even been inserted into the title of the second edition of a physics textbook by Harvey Brace Lemon. The title of the original edition, published in 1934, was From Galileo to Cosmic Rays, whereas the second edition, published in early 1946, was retitled From Galileo to the Nuclear Age.
Since those early days, the term nuclear age has been incorporated into almost every language as a designation for the international security system that has existed since 1945. Implicit in the term is the notion that the advent of nuclear weapons marked a far-reaching change from the system that existed until 1945. Although scholars have differed in their estimations of the extent to which the system has genuinely changed, few would deny that nuclear weapons have been one of the major elements in international politics since the mid-1940s.
Contending Ideas about Nuclear Weapons
The publication of a volume edited by Bernard Brodie, The Absolute Weapon: Atomic Power and World Order, in 1946 marked the first systematic attempt by specialists in international relations to think through the political and strategic implications of the nuclear age. Brodie and his colleagues—F. S. Dunn, P. E. Corbett, Arnold Wolfers, and W. T. R. Fox—sought to determine how warfare and international politics would be altered by nuclear weapons. Their findings pre-figured many of the themes that came up over the next several decades in scholarly and official analyses of nuclear arms. Brodie argued that nuclear weapons had made total war obsolete and that U.S. military strategy from then on would have to emphasize deterrence: "Thus far the chief purpose of our military establishment has been to win wars. From now on its chief purpose must be to avert them. It can have almost no other useful purpose" (p. 5). This view, which adumbrated the U.S.. shift to a declaratory policy of "massive retaliation" in the 1950s, was broadly accepted by the other contributors. Brodie and his colleagues left no doubt that, in their view, nuclear weapons had fundamentally changed the nature of world politics and military strategy.
The Soviet Union's acquisition of nuclear weapons in 1949, and the subsequent emergence of a U.S.-Soviet nuclear standoff, seemed to strengthen Brodie's basic point. Nonetheless, from an early stage, his thesis had many detractors. Some analysts argued that Brodie failed to take account of the importance of limited wars, such as those fought in Korea and Vietnam. In two highly acclaimed books, The Strategy of Conflict (1960) and Arms and Influence (1966), Thomas Schelling elaborated the theory of what he called "compellence," that is, the use of nuclear threats (and threats of the massive use of conventional weaponry) to coerce the adversary into taking a particular course of action. Schelling contended that nuclear deterrence did not eliminate the need for U.S. policymakers to deal with contingencies short of nuclear war and to think about how to use nuclear weapons to influence political and strategic outcomes.
Schelling also argued that even in relations between the two superpowers, strategy was not obsolete in the nuclear age. One of the other purposes of his books was to develop a better strategy for great-power competition within the context of deterrence. Schelling argued that deterrence of Soviet aggression in Europe or East Asia was crucially dependent on credibility. Unless the threat of retaliation was credible, Soviet leaders would have little reason to yield during a crisis. To cope with this problem, U.S. leaders, Schelling maintained, would have to demonstrate that they were prepared to act in ways that ordinarily would seem irrational. Schelling stressed that by actively preparing to carry out "threats that leave something to chance" (the title of a chapter in The Strategy of Conflict ), U.S. policymakers would bolster their own credibility and thereby reduce the chance that they would ever be forced to make good on those threats.
Other analysts went a good deal further than Schelling in contesting Brodie's views about nuclear weapons. Strategic analysts such as Herman Kahn in the 1960s and Colin Gray in the 1970s and 1980s rejected the whole notion of an "absolute weapon." Kahn and Gray contended that even large-scale nuclear warfare between the two superpowers was not "unthinkable." They acknowledged that nuclear weapons might induce greater caution on the part of policymakers, but they stressed that this did not mean that the chance of war was zero. On the contrary, Kahn and Gray argued, there was a possibility that nuclear war would break out, and therefore they believed that U.S. policymakers must be prepared to fight such a war and to win it. Gray summed up this view in an article he coauthored in 1980 with Keith Payne. The article stressed that "the United States must possess the ability to wage nuclear war rationally" and must develop "a plausible theory of how to win a war or at least insure an acceptable end to a war." Gray and Payne urged the U.S. government to "plan seriously for the actual conduct of nuclear war" and to develop a strategy "to defeat the Soviet Union and do so at a cost that would not prohibit U.S. recovery." As they saw it, a combination of robust strategic anti-missile and air defenses, a comprehensive civil defense program, and a large and diverse arsenal of nuclear missiles and bombers would ensure victory.
Not surprisingly, the views expressed by Kahn and Gray proved controversial. Stanley Kubrick satirized the nuclear war-fighting school in his 1964 film Dr. Strangelove. (Many viewers guessed that the title character was based on Kahn, but Kubrick never confirmed this.) More seriously, critics argued that theories of victory in a large-scale nuclear war rested on untenable assumptions about nuclear weapons and strategic defense technology. In a widely cited article published in early 1982, Wolfgang Panofsky and Spurgeon Keeny maintained that a "effective protection of the population against large-scale nuclear attack is not possible" and that an exchange involving only a few thousand of the more than fifty thousand nuclear weapons deployed by the United States and the Soviet Union "could destroy most of the urban population and destroy most of the industry of both sides." Even much smaller nuclear exchanges, they added, would have "very severe consequences." Nuclear war-winning strategies, in their view, were based on "wishful thinking."
Mutual Assured Destruction
Much of the intellectual debate about the U.S.-Soviet nuclear relationship was encapsulated in the perennial controversy about what became known as Mutual Assured Destruction (MAD). The concept of MAD was first enunciated in the early 1960s when both the United States and the Soviet Union began deploying large numbers of intercontinental-range ballistic missiles (ICBMs) armed with nuclear warheads. Defense Secretary Robert McNamara and other U.S. officials at the time argued that, in a situation of MAD, any large-scale use of nuclear weapons by either side would provoke retaliation in kind by the other side, resulting in the effective destruction of both. Under this logic, no rational leader on either side could hope to gain a meaningful advantage by starting a nuclear war, and therefore mutual deterrence would prevail. Many observers construed these statements as an accurate reflection of U.S. nuclear doctrine.
The intellectual debate about MAD often was reflected in concerns raised in public discussions and policy circles. The notion that, as Winston Churchill put it, the "safety" of each side rested on the prospect of "mutual annihilation" was a discomfiting one for many Americans. The vulnerability inherent in MAD was in contrast to the relative invulnerability that the United States had always enjoyed by virtue of its geography. The desire to move beyond MAD and restore a sense of invulnerability lay behind periodic attempts to build defenses against ICBMs and submarine-launched ballistic missiles (SLBMs) and to develop more credible nuclear war-fighting strategies. The Strategic Defense Initiative (SDI) of President Ronald Reagan's administration, announced in 1983 as a program to develop a comprehensive system of protection against ICBMs and SLBMs, was explicitly justified on the ground that indefinite reliance on MAD was too perilous an option.
Critics of these attempts to move beyond MAD, including Keeny and Panofsky, focused on two basic points. First, they argued that MAD was not a mutable doctrine but was instead a codification of the underlying strategic and technical realities. In their view, MAD followed from the technical nature of nuclear missiles and the inherent vulnerability of urban populations to nuclear destruction. No plausible doctrinal or technological innovations could alter this reality. Second, they maintained that attempts to move beyond MAD were dangerous because they would create the illusion that MAD was a doctrine and could be changed. This misperception, they contended, would increase the risk of nuclear war. Keeny and Panofsky argued that if policymakers erroneously believed it was possible to fight and win a nuclear war without suffering "unacceptable damage," they might be more willing to risk the use of nuclear weapons.
Unease about MAD also led in a very different direction. From the start of the nuclear age, a relatively small but vocal group of critics insisted that the only acceptable course of action was to ban all nuclear weapons. This school of thought was especially prevalent among scientists and intellectuals associated with the Bulletin of the Atomic Scientists, a specialized monthly publication that became famous for its doomsday clock on the cover. In later decades, many intellectuals supporting complete nuclear disarmament became active in banthe-bomb campaigns and the nuclear freeze movement. Jonathan Schell's best-selling The Fate of the Earth (1982), published at the height of the nuclear freeze movement in the early 1980s, laid out the case for the elimination of nuclear weapons. The book came under harsh criticism from many specialists on nuclear strategy and arms control, but it struck a chord with the U.S.. "peace" movement and with a considerable number of ordinary Americans who were concerned about the sharp increase in U.S.-Soviet tensions in the early 1980s. Not until the Cold War drew to an end in the late 1980s and early 1990s—and Washington and Moscow agreed to much sharper reductions in their strategic nuclear arsenals—did the antinuclear weapons movement wane in influence.
Nuclear Thinking in the Post–Cold War World
After the Soviet Union disintegrated at the end of 1991, the formerly antagonistic relationship between Moscow and Washington ceased to exist. The U.S.-Soviet nuclear standoff, which had dominated strategic thinking in the nuclear age, was no longer relevant. Instead, thinking about the nuclear age shifted mainly to issues of nuclear proliferation and efforts to prevent (or dissuade) non-nuclear weapons states from acquiring nuclear arms. Although the United States and post-Soviet Russia continued to possess large numbers of nuclear-armed ICBMs that were maintained at full alert, fears of a large-scale nuclear war all but disappeared. Instead, strategic analysts worried about the possibility of nuclear terrorism and nuclear weapons programs under way in so-called rogue states like North Korea, Libya, Iran, and Iraq under Saddam Hussein.
Some analysts, such as Kenneth Waltz and Shai Feldman, had long argued that nuclear proliferation should be welcomed rather than discouraged. Waltz maintained that nuclear weapons would enable relatively weak states to deter stronger and more aggressive neighbors from attacking them, in much the same way that the United States and the Soviet Union had relied on mutual deterrence to ensure peace between them. The "optimists" about nuclear proliferation (a label that was later attached to Waltz and others who shared his views) were never particularly numerous, however. In the post–Cold War world, the "pessimists" like Scott Sagan were far more common. In an illuminating exchange with Waltz, Sagan pointed to a number of dangers regarding potential accidents and unauthorized uses of nuclear weapons that would make nuclear war more likely, not less likely, in a proliferated world. Sagan and others also contended that nuclear proliferation would increase the risk that weapons might be diverted to terrorists.
Analysts who wanted to prevent nuclear proliferation differed in their views of how to achieve that goal. Some argued that unless the security concerns of proliferating states were allayed (or at least greatly mitigated), those states would be unlikely to forswear nuclear weapons. They cited the case of India and Pakistan, both of which openly acquired nuclear weapons in 1998 (though India had tested a nuclear bomb as far back as 1974), as an example of the pressures on states to build nuclear weapons in order to deter hostile neighbors. Analysts who subscribed to this view maintained that the best way to prevent nuclear proliferation was to address the underlying security concerns of potentially vulnerable states through international mediation. Other analysts wanted a more active policy to discourage nuclear proliferation. They advocated a "counterproliferation" strategy that would deal with regional security concerns but would also include a variety of sanctions against states that continued to pursue nuclear weapons programs. These sanctions would range from diplomatic pressure to condemnations by the UN Security Council to economic penalties and ultimately to military action. Scholars who believed that military action might, in the end, be desirable argued that Israel's successful raid in 1981 against Iraq's Osiraq nuclear plant underscored the importance of not ruling out the military option. Had Israeli jets not bombed the facility, Iraq most likely would have been able to build a nuclear weapon by the late 1980s, well before its program came under aggressive international scrutiny.
The prospect of nuclear terrorism was the other major issue of concern to specialists on nuclear weapons in the post–Cold War world. Contrary to popular wisdom, the threat of nuclear terrorism was not at all new. Concerns about the possibility that a nuclear bomb would be smuggled into a U.S. port had arisen as far back as the mid-1950s. Analysts such as Schelling, Brian Jenkins, and Paul Leventhal had written books and articles about the risk and implications of nuclear terrorism in the 1970s and 1980s. For the most part, however, the question of nuclear terrorism during the Cold War was generally overshadowed by the U.S.-Soviet nuclear standoff. Only in the post–Cold War world, when the U.S.-Soviet confrontation no longer dominated strategic thinking, did analysts devote much greater attention to the terrorist threat. This focus intensified, for understandable reasons, after the large-scale terrorist attacks on the United States on September 11, 2001.
Although experts on nuclear proliferation generally agreed that few if any terrorist groups had the wherewithal to build a nuclear weapon on their own, they warned that a weapon (or at least crucial components, including fissile material) might be furtively supplied to a terrorist group by a state like North Korea or by a group of rogue scientists. The nuclear-supply trail involving the nuclear weapons programs of both Pakistan and North Korea that came to light in 2004 reinforced these concerns. Most analysts believed that such channels could be closed through concerted international action, but they held out little hope that the risk could ever be fully eliminated. Thus, even after the Cold War ended, the perils of nuclear weapons continued to dominate thinking about the nuclear age.
See also Peace ; Technology ; War .
Brodie, Bernard, ed., The Absolute Weapon: Atomic Power and World Order. New York: Harcourt Brace, 1946.
Freedman, Lawrence. The Evolution of Nuclear Strategy. 3rd ed. New York: Palgrave Macmillan, 2003.
Gray, Colin S., and Keith B. Payne. "Victory Is Possible." Foreign Policy 39 (summer 1980): 14–27.
Herring, Eric, ed. Preventing the Use of Weapons of Mass Destruction. London and Portland, Ore.: Frank Cass, 2000.
Jenkins, Brian M. Will Terrorists Go Nuclear? Discussion Paper No. 64. Santa Monica, Calif.: California Seminar on Arms Control and Foreign Policy/RAND Corporation, 1975.
Kahn, Herman. Thinking about the Unthinkable. New York: Horizon Press, 1962.
——. On Thermonuclear War. Princeton, N.J.: Princeton University Press, 1960.
Kaplan, Fred M. The Wizards of Armageddon. New York: Simon and Schuster, 1983.
Keeny, Spurgeon M., Jr., and Wolfgang K. H. Panofsky. "MAD versus NUTS: Can Doctrine or Weaponry Remedy the Mutual Hostage Relationship of the Two Superpowers?" Foreign Affairs 60, no. 2 (winter 1981–1982): 287–304.
Sagan, Scott D., and Kenneth N. Waltz. The Spread of Nuclear Weapons: A Debate. New York: Norton, 1995.
——. The Strategy of Conflict. Cambridge, Mass.: Harvard University Press, 1960.
Waltz, Kenneth N. The Spread of Nuclear Weapons: More May Be Better. London: International Institute for Strategic Studies, 1981.