Over the past thirty years, the nuclear-arms race has been propelled by political tensions, by technical innovations, and by rivalries inside the governments of the United States and the Soviet Union. But at the moment, on the American side one overriding concern promotes the buildup of nuclear weapons—the fear that the United States might be denied its ability to inflict a devastating retaliatory blow if the Soviet Union struck first. This fear presumes that a nuclear war, far from being an act of mutual annihilation, might be a controllable, survivable, even "winnable" encounter, and that the Soviet Union may be better equipped than the United States to prevail in a nuclear war.
Such an anxiety, if well grounded, would compel any responsible American leader to search seriously for new nuclear-weapons projects, beginning with the MX missile and perhaps extending to antiballistic-missile systems and greater efforts for civil defense, in the hope of redressing the balance. The Reagan Administration, of course, is pushing ahead on several such fronts and says that it cannot persuade the Soviet Union to negotiate for reductions in strategic weapons unless we first show our determination to increase American strength. Even if the strategic-arms-reduction talks (START) that President Reagan has proposed eventually lead to an agreement, that welcome development would not come sooner than several years from now. In the meantime, American policy need not be driven by a fear of a Soviet first strike. Instead, it should rest on a recognition of the basic reality of the nuclear age: that the only option open to either the Soviet Union or the United States is deterrence. Given today's weapons, neither side can do anything to protect itself against the retaliatory threat the other poses; by the same logic, neither side need fear that its threat to the other will be called into question. This balance hardly justifies political or moral complacency. Because of the catastrophe that would occur if deterrence failed, our best efforts must be directed to preventing the circumstances in which nuclear-weapons would ever be used. But the concept of deterrence suggests a very different direction for American action from the one indicated by anticipation of a Soviet first strike.
The current era has often been spoken of as a "window of vulnerability," in which America's nuclear force is uniquely at risk. But it can instead be a "window of opportunity" in which to negotiate an end to the arms race. The most obvious and the most sensible step for the United States at the moment is to add nothing to our nuclear forces, and to seize this opportunity to press for a freeze on the development, testing, and deployment of all nuclear weapons and new delivery systems by each side.
As has happened before in the arms race, we have been told that technical progress has created a theoretical vulnerability for our force. The Soviet missile force has increased in size and accuracy, and supposedly poses fresh dangers to our land-based nuclear missiles. The Soviet Union's theoretical ability to destroy nearly all of these missiles in a surprise attack, it is argued, will psychologically upset the balance of deterrence, and will thereby make the United States vulnerable to Soviet blackmail. This will happen, it is further argued, even though the great majority of the American nuclear weapons are carried on bombers or by ballistic-missile submarines, rather than by the Minuteman and Titan missiles that are based in silos throughout the Midwest. An American President might be afraid to retaliate after a Soviet attack on the U.S. missiles, because the Soviet Union would then respond with a major attack on American cities. The conclusion of this line of reasoning is that the U.S. cannot contemplate any slackening of the pace until it has redressed the imbalance by building the MX missile or other systems.
I accepted this scenario myself until I made a few simple calculations concerning how vulnerable the Minuteman system actually is and what the strategic situation would be even if it were somehow totally destroyed. It emerges from any such calculation that neither side can escape the risk of devastating retaliation if it launches a pre-emptive attack. This is the only vital issue for each side—the actual capabilities for responding after attack, not guesses about what the other side's intentions might be. Intentions may change, and they are always difficult to discern. But the meaning of the capabilities is unambiguous: under present technology, either side could devastate the other after enduring any conceivable attack.
The U.S. has more deliverable nuclear warheads than the Soviet Union does. A 1978 study prepared for the Congressional Budget Office estimated that in the mid-1980s, when the "window of vulnerability" will allegedly stand open, the U.S. will have 13,904 warheads on its strategic delivery systems, versus 8,794 for the Soviet Union. The Soviet Union, for reasons we have never fully understood, has chosen to build missiles larger than ours, with larger warheads; and its force, though smaller in numbers, contains more "equivalent megatons" than ours does. (The measure "equivalent megaton" takes account of the fact that small nuclear warheads do proportionately more damage than large ones, since the area a warhead destroys does not increase linearly with the size of the warhead.) The same Congressional Budget Office study estimated that in the mid-1980s the U.S. force would represent 4,894 equivalent megatons, versus 8,792 for the Soviet Union. Paul Nitze, of the Committee on the Present Danger, which has been among the most strident of the groups warning about a window of vulnerability, has estimated that if both sides built up to the limits allowed by the SALT II treaty (whose ratification the committee opposed), the U.S. would have 12,504 nuclear warheads and the Soviet Union 11,728. It foresees roughly the same advantage for the Russians in equivalent megatons as does the Congressional Budget Office.
Of the 13,000 to 14,000 warheads projected for the American force, roughly 2,100 are on the Minuteman and Titan missiles. The land-based force represents some 1,507 equivalent megatons. Therefore, if every single Titan and Minuteman were destroyed in a successful surprise attack, the U.S. would be left with somewhere between 11,000 and 12,000 nuclear warheads. The submarine fleet would account for approximately 6,000 of these weapons, and the rest would be carried by bombers. All together, these remaining American warheads would represent about 3,500 equivalent megatons.
On planning American nuclear forces in the early 1960s, Robert McNamara came to the conclusion that 400 equivalent megatons would be sufficient to inflict unacceptable damage—and that the U.S. could have absolute confidence in its deterrent if it built such a retaliatory capacity three times over, once on the bomber fleet, once on land-based missiles, and once with the submarine force, for a total of 1,200 equivalent megatons. In other words, the 11,000 or 12,000 warheads, representing 3,500 equivalent megatons, that the U.S would retain even after a perfectly successful first strike against our land-based missiles would be three times larger than the force that was itself designed to be able thrice to destroy the Soviet Union. The accuracy of nuclear weapons has improved since McNamara's day, further increasing their effective power. These figures do not even count the several thousand American warheads that are left in Europe and other parts of the world, some of which could be used for retaliation.