¹ The term “first strike,” although generally it could be used to describe any initial attack whether on the enemy's forces or cities, normally refers to the attempt (or the presumed ability) to destroy large portions of the adversary's strategic forces before they are launched – hence a first strike is usually counterforce rather than countercity and is sometimes termed a “dis-arming strike.” “Damage limitation,” another term widely used in this paper, encom-passes the ability largely to prevent damage to oneself in a nuclear exchange. It can be achieved by deploying extensive defences, or by launching a first counterforce strike, or by a combination of both.

² A standard formulation. It occurs in a statement before the Committee on Armed Services, House of Representatives, Hearings on Military Posture, March 1966Google Scholar, 7326 and, more recently in McNamara, Robert S., The Essence of Security, New York, Harper and Row, 1968, 52.Google Scholar

³ Statement before the Senate Armed Services Committee on the Fiscal Years 1969–73 Defense Program and 1969 Defense Budget (Jan. 22, 1968), 47.Google Scholar

⁴ A standard formulation. Its latest occurrence is in a letter from Secretary of Defense, Melvin Laird, to Senator J. W. Fulbright (July 1, 1969), found in the Senate Committee on Foreign Relations hearings on Intelligence and the ABM (July 9, 1969), ix.Google Scholar

⁵ Laird to Fulbright, x–xi.

⁶ Statement by Secretary Laird, March 21, 1969 in Hearings before the Senate Subcommittee on International Organization and Disarmament Affairs on Strategic and Foreign Policy Implications of ABM Systems (March 1969), 196.Google Scholar

⁷ Secretary Laird's testimony, June 23, 1969, Intelligence and the ABM, 59.

⁸ Ibid., 52–9.

⁹ The accuracy of inter-continental ballistic missiles is measured by their circular error probable (CEP), the radius of a circle centred on the target within which half of the warheads are expected to land. The warheads’ destructive power is the product of a complex relationship between their accuracy, their yield, and the hardness of the target. When blast is the criterion, as in an attack on hard silos, the effects of improving accuracy are much greater than the effects of improving yield proportionately. For instance, a 1-megaton warhead with a CEP of two-tenth nautical miles would have an 85 per cent chance of destroying a silo hardened to withstand overpressure of 300 pounds per square inch – the generally conceded degree of hardening of American and Russian silos. If the warhead's accuracy were improved by a factor of two (a CEP of one-tenth nautical miles) the same kill probability would be achieved by a yield of 125 kilotons (a reduction in the yield by a factor of 8). Consequently, the bulk of recent research has concentrated on guidance systems to improve accuracy and, today, accuracy is the most important of several criteria (total yield, deliverable warheads, basing, etc.) for deciding the effectiveness of strategic forces. For an extended discussion of these issues see Strategic Survey 1969 (Institute for Strategic Studies), 30–3 and Smart, Ian, Advanced Strategic Missiles: A Short Guide, Adelphi Paper 63, Institute for Strategic Studies, Dec. 1969, 16–17.Google Scholar No public discussion of reprogramming capabilities in the Soviet Union and the United States, beyond the fact that both countries are working in this area, has come to my attention.

¹⁰ The doyen of the strategists favouring a posture of Defensive Emphasis is Donald G. Brennan of the Hudson Institute. See in particular Brennan, and Hoist, Johan J., Ballistic Missile Defences: Two Views, Adelphi Paper 43 (Nov. 1967)Google Scholar, and his “The Case for Missile Defense,” Foreign Affairs, XLVII, no 3 (April 1969), 433–48. I would like to acknowledge my large debt to him and to thank him for his help with this paper although he would differ strongly with some of its particular conclusions.

¹¹ Brennan, “The Case for Missile Defense,” 435–8.

¹² The formulation is Brennan's.

¹³ On this see Smart, Advanced Strategy Missiles, 28–9.

¹⁴ Project Janus is the name assigned to an ongoing study of such a system.

¹⁵ Second strike preserving options in addition to Safeguard include garage-mobile, rail-mobile and road-mobile Minutemen, hard-rock silos, multiple access silos, deep silos, increased numbers, diversified basing and deceptive basing. The MIRV is probably the ultimate in penetration aids but also quite competent are chaff to confuse radars by reflecting multiple signals, decoys to increase the number of targets with which a defender must contend, and various other measures to blind radars or interfere with their detection and tracking.

¹⁶ Hearings before the House Subcommittee on National Security Policy and Scientific Developments on Diplomatic and Strategic Impact of Multiple Warhead Missiles (Oct. 9, 1969), 5.Google Scholar On this issue see also Marzari, F., “The Derangement of MIRV,” International Journal, Autumn 1971.Google Scholar

¹⁷ These figures do not include those United States tactical nuclear weapons or aircraft in Europe with sufficient range to reach western portions of the Soviet Union.

¹⁸ Strategic Survey 1969, 27–8.

¹⁹ Their superiority is generally acknowledged in the area of guidance technology, warhead construction, and radars. The fact that Soviet missiles are fuelled in the main by storable liquid propellents (only the sixty ss-13s are solid fuelled, unlike almost the totality of the United States force) is generally considered irrelevant. This seems to be true only up to a point. Depending on the technology, some liquid fuel systems may be more delicate to maintain and slower reacting in which case the pressure to get them off the ground at the first sign of attack is comparatively greater. A related point is that missiles equipped with multiple warheads may equally increase the pressure for a launch-on-warning posture. Riding out an attack on the ground at the risk of losing several warheads to one attacking missile can look like a bad proposition.

²⁰ There is no public evidence on this issue beyond statements by administration officials that upgrading may be possible. See Diplomatic and Strategic Impact of Multiple Warhead Missiles, 3.

²¹ Bull, Hedley, “Arms Control: a Stocktaking and Prospectus,” Problems of Modern Strategy, Part II, Adelphi Paper 55 (March 1969), 13.Google Scholar

²² Diplomatic and Strategic Impact of Multiple Warhead Missiles, 3.

²³ The New York Times, July 25, and August 17, 1970. The finesse, even if successful, may be the wrong play for the administration. If the United States accepts zero ABMS in exchange for a freeze on the deployment of ss-9s at the current level, about 300, will not Minuteman be threatened the moment the ss-9 acquires multiple independently targeted warheads with accuracy comparable to present American systems? Even in its own terms, the administration's logic is tortuous unless one assumes, against the evidence, that the next step would be a proposal to ban MIRVS.

²⁴ On this see Bull, “Arms Control,” 15.

²⁵ For a comprehensive list see Scoville, Herbert Jr., Towards a Strategic Arms Limitation Agreement (New York, 1970).Google Scholar For a fuller discussion of the issues raised by the SALTalks see Marzari, F., “The Prospects for SALT,” Canadian Defence Quarterly, Fall 1971.Google Scholar

²⁶ On this see Kintner, William R., “The Uncertain Strategic Balance in the 1970s,” Arms Control and National Security, I (1969), 34–6.Google Scholar