The End of the Balance of Terror?

ANTI-MISSILE MISSILE

By LAWRENCE MARTIN

CI IN CE the dawn of the missile age there has ',been speculation that an answer to the missile might arise. Yet the task of intercepting ballistic missiles seemed for many years to be a hopeless one and it became popular to remark that the task was equivalent to attempting to hit a fly in space. Recent developments, however, some of which have taken place in the West only within the past two years, have created an excited belief amongst those who have been privy to them that this difficult task may be on the verge of accom- plishment. This has quite naturally aroused un- certainty and anxiety as to the consequences that would arise if the missile could no longer be relied upon to get through; that is, if this hitherto supposedly absolute weapon, on which the balance of terror and the maintenance of peace between the superpowers have depended, ceased to enjoy its old ascendancy.

What is involved may perhaps best be approached through a description of American efforts in this direction. There are in theory three distinctive periods during which a missile may be intercepted: when it is being launched, when it is in mid-course, and terminally when it begins to re-enter the atmosphere at something like 400,000 feet, travelling at 20,000 feet per second and some thirty to forty seconds away from the moment of its impact on the target. Various efforts at developing systems for intercepting missiles upon their launch have proved to be hopelessly uneconomic, although the possibility that some launch interception of submarine bal- listic missiles might be achieved should not be wholly dismissed.

In the late 1950s the United States Army con- centrated its efforts upon developing the Nike- Zeus anti-missile designed to make its intercep- tions very early in the terminal phase of the in- coming warhead. This missile proved capable of successfully intercepting missiles fired against it, but it was not put into production because of the belief that it would be incapable of discriminat- ing between a real warhead and decoys that the opposing side might use with the intention of confusing the defence. It must be understood that at that time, and, so far as we are aware, at present also, the Soviet Union had not created an operational decoy system. But it is well known that there are several devices by which a defence can theoretically be confused, although this task is not as easy as is sometimes assumed. It is pos- sible, for instance, to design a warhead to distribute a large number of lightweight simula- tions of itself that scatter over a wide area as they travel towards the target.

As a result of grave doubts as to the efficacy of the Nike-Zeus system against such counter- measures, one of the important negative decisions of modern military history was taken in 1959 when it was decided not to proceed with deployment of the Nike-Zeus system. Research and development on such systems has, however, gone ahead energetically during the intervening period and the United States has spent some- thing of the order of $400 million a year upon it. At the same time about $120 million has been spent on Project Defender, a study of methods of Lawrence Martin is Professor of International Relations at the University College of Wales, Aberystwyth. discriminating re-entering vehicles, and both the United States Navy and Air Force have vigorously pursued programmes designed to im- prove the capacity of their own warheads to penetrate enemy defences. Such studies of pene- tration aids are, of course, reciprocal and com- plementary to efforts at defence.

The next phase in the effort to discriminate be- tween real and simulated warheads concentrated upon postponing interception until incoming objects had penetrated a considerable proportion of the atmosphere. Once within the atmosphere it becomes more difficult to design cheap, light decoy devices that behave in a similar manner to the real thing. To intercept at such a late stage, however, it is obviously necessary to have a defensive weapon that can react quickly and so a missile of very high acceleration, appropriately named Sprint, was developed for the purpose and linked to the rapidly improving radar computa- tion devices. The development of 'phased array' antennae for radar makes it possible to scan the horizon very rapidly indeed, so that the capacity of the detection system is almost infinite and limited only by the ability of the computation devices to assess and interpret the information. Very large high-speed computers have brought corresponding advances in the latter field so that the new radar and discrimination systems asso- ciated with sophisticated anti-ballistic missile systems are capable of remarkable feats of identification and discrimination of targets.

Very late interception has, however, draw- backs that cannot be overcome. The closeness of the interception to the ground places strict limitations on the size of the nuclear anti-missile warhead that can be used without causing de- struction on the surface, and this, combined with the effect of the atmosphere upon the destructive energy released by the explosion, would result in a relatively small radius of kill, measured perhaps in fractions of a mile. The lateness of the inter- ception also makes it necessary to locate the defensive system very close to the point which it is intended to defend. Thus a widespread system of defence would be extremely expensive, while a more modest system would only be capable of defending selected points. The consequent oppor- tunity for the enemy to saturate the defence by firing at a widely scattered range of targets or to adopt a groundburst far from the target, with the intention of using fallout as a destructive mechanism, renders the anti-missile missile rela- tively unsatisfactory as a way of defending popu- lations, although it may serve to protect particu- larly valuable military installations.

Within the last two years, however, we have entered a period of new technological thinking which some believe may give entirely new promise to the anti-missile effort. The fundamen- tal change here is the decision to concentrate upon a new method of killing warheads. This change rests upon an increased realisation of the fact that much of the radiation energy released by a nuclear warhead is transmuted by the atmo- sphere into relatively short-range forms of energy such as heat and blast. The same warhead when detonated in space may, by various radiation effects, and particularly by the effect of X-rays, release an instantaneous but very widespread de- structive energy, so that by virtue of the added consideration that increased altitude of detona- tion will permit use of very much bigger war- heads—measured in megatons—destructive radii may extend to many miles. Given this achieve- ment, the problem of discriminating the real from the false re-entry vehicle becomes much less acute, as it is then possible not merely to elimin- ate that part of the incoming cluster of objects that analysis suggests may be most dangerous but simply to clear the whole 'threat tube' indicated by the radar.

This achievement is the more significant as there are only a finite number of 'threat tubes' for any given target area. Such a system could still be saturated by the repeated firing of salvos, but nevertheless the fact remains true that the use of interception in space with large radii of kill makes it possible to consider the provision of a • thin defence for large areas rather than a tight defence for precise points.

Before any consideration of the significance of this theoretical and technological break- through for an American decision to develop and deploy anti-ballistic missile systems of this type, we must briefly consider Soviet progress in the same field. It is now generally accepted that the Soviet Union has been engaged in an inten- sive effort to develop anti-ballistic missile systems at its test area at Sary Shagan in Kazakhstan, and that the last series of atmo- spheric tests conducted by the Soviet Union was partly directed to this end.

Although initial Soviet claims of success were received with some scepticism in the West, in May 1964 the Soviet Union revealed a very large missile, known as the Galosh, that is believed to be capable of interceptions in ranges of up to 200 miles. In May 1965 Moscow television showed what purported to be a film of the launch of one of these missiles and in the following July Mr Brezhnev remarked that the Soviet Union had made 'important steps recently' in anti- missile development. Finally, last November, Marshal Krylov declared that the Soviet Union was now capable of mid-course interception of intercontinental ballistic missiles. It is possible that the present Russian system is not a fully operational one as we understand the term, but the Soviet anti-missile programme at the very least suggesti that there is something to be said for an American anti-missile effort and arouses the fear that the Soviet Union might achieve an effective deployment first.

It is, however, not the Soviet Union but Com- munist China that has played the most notable part in giving new hope to the advocates of a major American deployment of an anti-missile system. A 'threat analysis' study conducted by the Stanford Research Institute, and completed in January 1965, paid considerable attention to the significance for an American anti-missile pro- gramme of the Chinese development of nuclear weapons and came to the firm conclusion that the deployment of an anti-missile system would result in an almost complete defence against any potential Chinese attack in the next one or two decades. This would render the United States immune to Chinese deterrent threats and hence, it was argued, enable America to continue to extend the protection of its deterrent over allies in the Far East.

It is this capacity to argue the case for the anti- missile missile in the Chinese context that led the United States Army, which is the sponsor of the leading anti-missile system, to be extremely optimistic during the past eighteen months that it could persuade the Secretary of Defence to spon- sor a thin deployment of anti-missile systems costing between eight and ten billion dollars; such a thin deployment would consist of the Sprint missile point defence of cities and military installations, of the Nike-Zeus system revived for interception in space to provide thin area defence for the whole country, and of the deployment of a new short-range missile for the protection of key points, including the anti-missile sites, against aircraft, cruise missiles and submarine-launched missiles. This combination is now referred to as the Nike-X system.

In the new political and technological context the Joint Chiefs of Staff were able to agree for the first time in the summer of 1965 to advocate an anti-missile package unanimously to the Secre- tary of Defence. We now know, as a result of the presentation of the fiscal 1967 military budget to the Congress, that Secretary McNamara has resisted this request and has merely agreed to continue research and development upon a large scale. There are many who believe that the decision against deployment at this time was largely made not on the merits of the system itself, but merely as a result of financial stringency imposed by the unexpected expense of the operation in Vietnam.

But the negative decision was no longer made in the same terms as those of earlier years. No longer is it argued even by opponents of anti- missile deployment that it is impossible to develop and deploy a system capable of large- scale interception. In the new circumstances the case against deployment rests upon, on the one hand, a dispute as to whether this would be the most effective way in which to spend money as compared to other military programmes, includ- ing an expansion of the striking force intended to penetrate the defence of the other side, and, on the other hand, upon `political' considerations.

As the technical prospects for anti-missile de- fence have improved, considerable alarm has been expressed about the possible deleterious strategic and political effects of such systems. One of the more prominent expressions of such anxiety was that in a memorandum presented by Jerome Wiesner to the White House Conference on International Co-operation when he spoke of the 'heightened risks of a violent spasm of pro- curement—one spurring to new levels the cost, distrust and explosive dangers of an unending competition in arms.'

An appreciation of the roots of this anxiety depends upon a consideration of the ingredients of modern deterrent policies. A deterrent posture is now thought to be composed, in American terminology, of two elements, 'Assured Destruc- tion' and 'Damage Limitation.' The first of these is an assured capacity to do unacceptable dam- age to one's opponent and hence to deter his attack. The second is the capacity to limit the damage—which must nevertheless be accepted as disastrous—that would be done to one's own nation if deterrence fails. It is apparent that these two elements in the policies of two opposing powers are reciprocal, and that the success of one power in Damage Limitation must imply a reduction in the capacity of the other side to achieve Assured Destruction.

The instruments of Assured Destruction are the missiles and the bombers with which the attack is made and particularly those elements that are invulnerable, or relatively so, to a first strike. Instruments of Damage Limitation are civil defence, particularly shelters, strategic offensive forces, with which one may attempt to eliminate some offensive enemy weapons before they can be used, anti-submarine measures with which one attacks seaborne striking forces, de- fences against bomber attack and, finally, the anti-missile missile. If an anti-missile system were significantly to impair the Assured Destruction capacity of one state, it is argued that the capacity of that state to exercise deter- rence would become much less certain and that the state in question might therefore be encouraged to increase sharply its investment in offensive weapons in an attempt to offset its new disadvantage. The result of this, the argument goes, would be a new and possibly unending spiral in an arms race which might otherwise be stabilised at present levels of mutual vulnerability.

The plausibility of these anxieties depends, of course, upon the capacity of the anti-missile systems that are at present conceivable. Anti- missile defence for protection of retaliatory forces against pre-emptive attack has hitherto been regarded as hopelessly uncompetitive in cost with the alternative of multiplying the number of retaliatory weapons. It is now argued by some who have the best knowledge of the relative costs that the two alternative's are financially `in the same ball park.' To choose the anti-missile alter- native would do nothing directly to undermine the Assured Destruction capability of an oppon- ent but such a venture would get nations into the business of deploying anti-missile systems and thus conceivably facilitate a later extension to deployment in defence of cities.

As a damage-limiting device for cities an anti- missile system would be only part of a mix of de- fensive measures and could certainly not provide complete protection against all attack. Bombers and cruise missiles capable of penetrating beneath the defensive cover might acquire new signifi- cance. Thus the effects of an anti-missile defence for cities will depend very much upon the res- ponse that the enemy makes to its deployment.

Studies made available by the United States government in the last annual presentation of the Secretary of Defence to the Congress gave some precision as to what the United States might

achieve by anti-missile defence. Assuming a United States population of 210 million in a de- cade, then the estimated casualties from an all- out attack by Soviet forces, projected from present Soviet programmes, against a United States using similar defences to those now in use, might be expected to produce 130 million casualties if the Soviet Union struck first. The expenditure of $3.4 billion on a fall- out shelter programme might reduce this to 110 million. If the United States were to strike first, then expected casualties from Soviet re- taliation would be reduced from 100 million to 90 million by the fall-out shelter programme. Were the United States to spend $22.5 billion on an anti-ballistic missile system and other damage-limiting systems such as a bomber defence, and to add $2 billion to its ex- penditure upon strike forces, then American casualties might fall as low as 80-90 million in the event of a Soviet first strike. In the event of an American first strike, however, the new expendi- ture could result in American casualties coming down to between 25 and 40 million.

If one assumes, as one probably must, that the Soviet Union made a big effort to overcome these American defences, then even if United States expenditure rose to $24.8 billion on Damage Limitation and $6 billion more on strike forces, American casualties in the event of a Soviet first strike would still rise above 100 million. Even an expenditure of $32.2 billion on Damage Limitation would not reduce American casualties below, at the lowest, 75 million. Were the United States to strike first, however, these higher orders of defence expenditure could keep American casualties down to between 35 and 55 million.

It is in view of these depressing figures that the United States obviously has to ask very seriously whether such expenditures are worthwhile.

(To be concluded next week)