In August 2019, the United States withdrew from the landmark INF Treaty of 1987. Another crucial arms control treaty, the New START agreement, is set to expire in early 2021. Almost 50 years ago, the United States and the Soviet Union had started the process of strategic arms control negotiations. In May 1972, Richard Nixon and Leonid Brezhnev signed the Strategic Arms Limitation Treaty (SALT I) and the Anti-Ballistic Missile Treaty (ABM) at the Moscow Summit. [1] For the first time in history, the United States and the Soviet Union found agreement to limit the size of their strategic nuclear forces. The SALT I agreement set numerical limits on strategic weapons.

However, SALT I was an imperfect arms control agreement as it allowed qualitative improvement such as further deployments of hydra-headed strategic weapons with multiple warheads, the so-called MIRVs (Multiple Independently Targeted Reentry Vehicles). MIRVs were a new technology that allowed for a nuclear delivery vehicle to be loaded with several nuclear warheads, each directed at a different target: One missile would split into several nuclear warheads, and they would in turn hit separate targets more or less simultaneously. The MIRV technology enabled the United States to double or triple the number of warheads placed on existing missile sites. President Richard Nixon and National Security Adviser Henry Kissinger gambled on these technological advances a cost-effective way of increasing American firepower, providing "more bang for the buck." [2] The problem with MIRVs was that their deployment threatened to undercut the kind of strategic stability that US and Soviet policymakers were seeking. Due to the high accuracy, each side just needed to fire just a couple of MIRVed missiles to wipe out a decisive number of the other side's nuclear forces. In the age of MIRVs, the attacker gained a decisively superior position: MIRVs put a premium on surprise and preemption in a crisis. [3] The results of the SALT process were ambivalent. On the one hand, SALT achieved a stabilization of the international system. On the other hand, it institutionalized the arms race and put it "into the permitted channels." [4]

David Ambrose and David Tal wrote two timely, well-researched and finely articulated accounts on the history of the SALT process of arms control. Broad in scope and drawing from an impressive wealth of archival sources, both books detail how technology and personality influenced US and Soviet arms control policies. The single biggest dissimilarity between both books is that they come to differing conclusions: Ambrose sees SALT as "a deeply flawed process" (221) because of the level of arms reductions achieved. [5] To Tal, though, SALT was not primarily about reductions or limitations of weapons: He sees SALT as an effort to stabilize the international system.

Ambrose's approach discusses SALT within the wider context of US nuclear strategy. He argues that "perhaps SALT's gravest flaw was that if froze the strategic balance in a suboptimal way. Like a broken bone not properly set, it began to heal around a partially dysfunctional system of technology and doctrines" (216). Ambrose values SALT as a laboratory for future arms control negotiations though: The failure of SALT, he argues, helped to make things better in the next rounds of the arms control negotiations.

Tal has a different understanding of SALT. He argues that the SALT negotiations were not primarily about actual reductions or limitation of strategic arms. Rather, Tal contends that SALT was aimed at giving both sides a sense of equality and parity that would not force them to engage in a costly and unchecked arms competition. He emphasizes that SALT was never aimed ending the development of more destructive and more powerful weapons such as MIRVs and Cruise Missiles: "All in all, it seems the right conclusion to draw on SALT will be to suggest that, more than substance, its real meaning was appearance, domestically and externally. Externally, it was a barometer of American and Soviet relations, a symbol of coexistence, or the lack of it. The negotiations and agreements indicated that the two great powers, rival and competitors, could talk and agree. That the agreement had less substance was less important, appearance mattered more" (282).

Ambrose provides a broad interpretation of SALT: He is interested more in the grand scheme of things than in the nuts and bolts of the SALT negotiations and in the details and people. It is astonishing though that Ambrose did not use the materials at the Nixon Presidential Library. Neither did he use the rich evidence from the Nixon Tapes. Through further research, Ambrose would have gained a better understanding of Richard Nixon's and Henry Kissinger's use of linkage as a way to connect SALT with other issues of détente and global US-Soviet competition. Like many historians before him, Ambrose emphasizes that Nixon and Kissinger were trying to exact a price from the Soviet Union in return for SALT. However, Ambrose's treatment of linkage is incomplete. The delay in the opening of the SALT negotiations was not a result of Nixon's and Kissinger's reluctance "to set a date too soon" (36), but because they tried to receive concessions from the Soviet Union in return for the beginning of the talks. Nixon's and Kissinger's idea was to make progress in SALT dependent on Soviet help to disengage the United States from Vietnam. The linkage approach complicated US-Soviet cooperation. Vietnam was not a suitable issue on which to test Soviet credibility. Apart from arms supplies, the USSR's ability to influence the North Vietnamese in the peace talks with the United States was limited. As David Tal points out "Nixon was proud of the usefulness and innovation of the linkage, but for no real reason. To start with, the assumption that the Soviets were so eager to have an arms control agreement that they would pay the price the United States was planning to exact from them was completely wrong" (8). Thus, as Tal points out, the linkage concept began to crumble over time.

Tal's and Ambrose's books also differ in their treatment of Henry Kissinger's backchannel negotiations with Anatoly Dobrynin, the mighty long-time Soviet Ambassador in Washington. Ambrose implies that the backchannel negotiations were less important and merely covered random issue areas. He writes that "Kissinger's attempts to negotiate alone with the entire upper echelons of the Soviet government requires considerable self-confidence and little room of error. The effects of the backchannel on the SALT negotiations and the strategic outcomes of the treaty were primarily restricted to the issue of submarines and summit negotiations" (47). This is not the case. Ambrose's statements are astonishing. Kissinger did not attempt to negotiate - he did negotiate, and he negotiated everything including the ABM limit agreement and the limit of offensive weapons. The Kissinger-Dobrynin backchannel was the single most important forum of US-Soviet leadership communication. [6] The American and Soviet delegations later turned the results of these backchannel discussions into articles and treaty clauses. Part of the explanation for Ambrose's view may lay in the fact that he did not exhaust all available sources on SALT such as the National Security Council materials at the Richard Nixon Presidential Library, at the US National Archives as well as the Digital National Security Archive.

Drawing from these important sources, David Tal's book provides a detailed account on the Kissinger-Dobrynin backchannel. Tal writes that "the new year 1971 had begun with SALT entering into a new phase - the making of the Kissinger-Dobrynin backchannel the prime channel for the arms control negotiations" (52). In January 1971, Kissinger announced that President Nixon was ready to negotiate a separate ABM agreement while at the same time both sides would continue their discussions on the limitations of offensive arms. Nixon's suggestion was the Kissinger and Dobrynin would work out the framework of the agreement before the opening date of the next round of the SALT negotiations between the US and Soviet delegations in March 1971. Nixon and Kissinger usurped the talks from the State Department and the Arms Control and Disarmament Agency (ACDA). Tal offers a well-researched account on the change in the US position leading from "stalemate to breakthrough" in the SALT talks (chapter 3, 50-69). On 23 April 1971, at instructions of the Soviet leadership, Dobrynin finally accepted Kissinger's idea that offensive limitations could be discussed before an ABM agreement was completed. Thus "the United States accepted a separate ABM agreement while the Soviet Union accepted the need to accompany it with some constraints on offensive weapons." [7] Nixon announced the agreement with great fanfare on 20 May 1971.

Both books differ in scope. Tal's account ends with the fall of SALT II in 1979. Ambrose's narrative provides rich details on the SALT negotiations during the Carter years. His account gives the reader a good sense of the intricate arms control problems confronting Ronald Reagan when he assumed office in 1981. Ambrose's book includes the START and INF negotiations and thus makes a case for incorporating arms control issues more directly into our narratives of the later stages of the Cold War. His book makes a highly technical subject accessible for a more general readership. Ambrose's focus on SALT verification issues is a case in point. Verification is again a key contemporary issue against the backdrop of the Obama-era nuclear agreement with Iran and ongoing discussions regarding U.S.-North Korea relations. Ambrose rightly points out that "verification is one of the most important and unexamined aspects of this process and indeed of the process of diplomacy and state making in general" (7). He emphasizes: "The roots of the basic concept and the modern politics and practice of treaty verification can be traced to the provisions of SALT II" (125). As a case in point, Ambrose refers to the evolution of U.S. schemes to verify and distinguish among Soviet MIRV missiles.

As a reviewer, I would have liked to see more on the domestic and public opinion side of SALT in both books. US public opposition to SALT caused enormous domestic furor. The end of SALT had as much to do with the reconfiguration of the U.S. domestic political scene as it did with the crisis in US-Soviet relations. Nixon and Kissinger failed to explain to the public why the SALT I Treaty permitted the United States to possess less missile launchers compared to the Soviet Union. The overall aggregate was 2,347 Soviet launchers vs. 1,710 U.S. launchers. Public critics saw SALT I as a Soviet victory. It was not sufficiently understood in public that SALT I gave the United States superiority in terms of the overall aggregate of warheads (as long as the Soviets did not deploy MIRVs). Due to the MIRV technology, the 1710 American ICBMs and SLBMs permitted in SALT added up to about 5900 warheads compared to an aggregate of 3700.

David Tal's book looks into the rising domestic criticism of SALT: Critics such as Senator Henry Jackson argued that SALT I gave the Soviet Union a permanent advantage in heavy Intercontinental Ballistic Missiles while the US margin in the number of warheads would be transitory as it was predictable that the Soviet Union would soon produce its own MIRVed missiles. In the summer of 1972, Jackson introduced a SALT amendment in Congress stipulating that the objective for SALT II should be to reach a level of strategic forces that would at least equal the Soviet Union's capabilities in strategic arms. Moreover, Jackson brought Nixon and Kissinger to reprimand the arms control officials that were involved in the SALT negotiations. They were replaced by arms control skeptics. In 1974, the Soviet leadership saved SALT through considerable concessions at the Vladivostok summit. Leonid Brezhnev agreed to a common MIRV ceiling of 1320 launchers on the occasion of the first meeting with Gerald Ford. However, Ford shied away from seeking the conclusion of SALT II. He was not prepared to wage a public debate over SALT.

Last but not least, Ambrose's and Tal's books challenge the dominance of rational deterrence theory as the presumed best approach for interpreting US nuclear policy. Both offer an inductive, detail-oriented approach of their own discipline of international history. Both books underline that nuclear choices cannot be analyzed in isolation from the broader politics of the day. Arms control and nuclear strategy is what policymakers make of it. Both books underscore that personality matters a great deal: The President's and his top aides' subjective perceptions of nuclear deterrence dynamics mattered even more in light of the ever-increasing dominance of the White House over the rest of the executive branch. At the same time, both books emphasize the limits of presidential power. Tal refers to Jimmy Carter and Richard Nixon as cases in point: Tal writes that "President Jimmy Carter viewed SALT differently from his predecessors. He thought that it should be more than an agreement driven by pragmatic, balance-of-power considerations. Driven by faith and ideals, Carter wanted SALT to represent a real change in the attitude to nuclear weapons, to really reduce their threat, and to negotiate an agreement that would be a first step toward a major reduction of the nuclear arsenal the two great powers possessed. Just like Nixon, Carter declined the history of the negotiations, and intended to present new ideas, his ideas. And just like Nixon, he failed. It soon became clear pretty that the making of foreign policy in general, and arms control in particular, cannot be made by a single person, even if he is the leader of the strongest nation on earth" (271).

Notes:

[1] For a most recent account, see Arvid Schors: Doppelter Boden. Die SALT-Verhandlungen 1963-1979, Göttingen 2016.

[2] Francis Gavin: Nuclear Nixon: Ironies, Puzzles, and the Triumph of Realpolitik, in: Fredrik Logevall / Andrew Preston (eds): Nixon in the World. American Foreign Relations, 1969-1977, Oxford / New York 2008, 126-145; David Tal: "Absolutes" and "Stages" in the Making and Application of Nixon's SALT Policy, in: Diplomatic History 37 (2013), 1090-1116.

[3] For the context, see Francis J. Gavin: Nuclear Statecraft. History and Strategy in America's Atomic Age, Ithaca / London 2012; James E. Goodby: At the Borderline of Armageddon. How American Presidents Managed the Atom Bomb, Lanham, MD 2006; McGeorge Bundy: Danger and Survival. Choices about the Bomb in the First Fifty Years, New York 1988.

[4] See Foreign Relations of the United States, 1969-1976, Vol. XXXII, SALT I 1969-1972, Washington, DC 2010, 93; See Stephan Kieninger: "Diverting the Arms Race into the Permitted Channels." The Nixon Administration, the MIRV-Mistake, and the SALT Negotiations, Woodrow Wilson International Center for Scholars, Nuclear Proliferation International History Project, Working Paper #9, Washington, DC 2016.

[5] For the context, see Jussi Hanhimäki: The Flawed Architect. Henry Kissinger and American Foreign Policy, Oxford / New York 2004.

[6] See Richard A. Moss: Nixon's Back Channel to Moscow. Confidential Diplomacy and Détente, Lexington, KY 2017.

[7] See Raymond L. Garthoff: Détente and Confrontation. American-Soviet Relations from Nixon to Reagan, Washington, DC 1994, 167.

Stephan Kieninger