Alexander Lanoszka’s thoughtful book, Atomic Assurance: The Alliance Politics of Nuclear Proliferation, seeks to answer the question how alliances can best reduce the risk of nuclear proliferation. Its focus is on the tools at the disposal of a guarantor of extended nuclear deterrence, how it can curb the efforts of allies to acquire nuclear weapons, and possibly reverse their efforts (10). Lanoszka traces the link between U.S. alliance policies and (non)proliferation in three Cold War case studies of U.S. allies: West Germany (1954-1970); Japan (1952-1980); and South Korea (1968-1980). An additional chapter with five other cases of Cold War U.S. alignments with actual (Great Britain, France) and aspiring (Norway, Australia, Taiwan) proliferators further substantiates the argument. In the book, Lanoszka puts forward five propositions: military alliances might not keep allies from seeking nuclear weapons; the guarantor’s in theater conventional forces are crucial to reassure the ally; U.S. coercion of actual or potential proliferators plays less of a role than is assumed; economic or technological reliance of a security dependent ally instead works better to reverse or halt a program; and deterring an ally from initiating a program is easier than terminating one that is already underway (10).
This review was originally published on June 1st 2020 and is part of a larger article on the H-Diplo/ISSF Roundtable 11-17 on Lanoszka. Atomic Assurance: The Alliance Politics of Nuclear Proliferation.
The book’s central and most powerful argument is that the foreign policy doctrine and conventional military deployments of the U.S. play a decisive role in reassuring its allies. Lanoszka convincingly shows across multiple cases in Europe and Asia how allies were persuaded by the physical presence of U.S. forward deployed forces that the U.S. had “skin in the game” (15, 27), and this dissuaded them from pursuing nuclear weapons.
Extended nuclear deterrence remains a fascinating and difficult problem to grapple with, both from the perspective of the guarantor and from that of the ally. Glenn Snyder’s ‘alliance dilemma’ addresses the problem to some extent: allies face the dual risks that the other will abandon them at the time of conflict or conversely drag them into a conflict not in their interest. However, when it comes to alliances that involve nuclear weapons, the alliance dilemma only partially captures the extent of the problem. The potential costs of entrapment for the guarantor are extremely severe, and the costs and benefits are distributed unevenly between guarantor and allies. To believe that a state will risk not only its armed forces but the very survival of its society on behalf of an ally’s security is an inherently dubious proposition. It then stands to reason that an ally would be motivated to acquire its own nuclear weapon and to independently ensure its security (16). This particular problem is perfectly captured in the often-cited anecdote in which President Charles De Gaulle asked President Dwight Eisenhower whether he would be willing to sacrifice American cities for Paris, Brussels, or Berlin (139). Indeed, the French leadership could not believe that nuclear deterrence could encompass anything but vital national interests, and consequently they successfully pursued an autonomous deterrent for France (138-140). In fact, U.S. officials themselves hardly believed it: Lanoszka cites Eisenhower’s own doubts whether the U.S. would actually use nuclear weapons for anything other than the defense of the U.S. (55). Forward-based forces ensured the U.S. had sunk costs in allied security (16), and consequently signaled that the U.S. might be willing to make the ultimate sacrifice on their behalf. 
To clarify the linkages between nuclear strategy, conventional force posture, alliance politics, and proliferation is the book’s most valuable contribution. While Lanoszka does not suggest this is a new insight, in Atomic Assurance he makes the argument in a structured and comparative manner by process tracing the decisions of policymakers in the three main cases. The empirics are convincing and the policy outcomes are weighed against the rival explanations of the level of the threat from the adversary, domestic politics, and national prestige (22-25).
Particularly revealing is how the book shows that allies did not – and do not – have a static perception of the U.S. commitment to their security, but one that varied over time. The possibility of (re)initiating indigenous nuclear programs never entirely disappeared. The book contains evocative examples from the cases: for example, an unsubstantiated 1956 report in the New York Times about the withdrawal of U.S. forces was enough to prompt German Chancellor Konrad Adenauer to initiate talks with France and Italy for a joint nuclear program (57-58). The problem of extended nuclear deterrence is also not one that is confined to the Cold War era: President Donald Trump has threatened to move forces from the territories of European and Asian allies, and thereby triggered some to reconsider their non-proliferation stances. Atomic Assurance is therefore an important and also, unfortunately, a timely book.
This does not mean that, despite that important and welcome contribution, the book does not have some issues. The main one is how generalizable the theory is. Lanoszka purports to offer a “rigorous and predictive” (14) theory of the alliance policies available to an unspecified, generic guarantor to prevent proliferation. Just a few examples from the text that signal this ambition: “guarantors like” (6, 63), “the guarantor” (6, 18); “a guarantor” (155). It suggests that the book not only examines multiple cases of guarantors, but that multiple cases exist to can be examined.
However, how many guarantors of extended nuclear deterrence can we find besides the United States and how many alliances “like NATO” (155) have existed? In the final chapter, the book briefly examines the two other nuclear powers that extended nuclear deterrence to their allies: the Soviet Union and China. Yet, it only devotes one page (155-156) to them and does not explicitly address all the propositions or the alternative explanations that have previously been identified. One feels a missed opportunity of sorts. At the very least the book would need to provide more justification for why the Soviet Union and China cannot tell us much about the alliance policies of guarantors. This creates some tension within the book between the objective of making a more general argument and picking apart the patterns in Cold War U.S. alliance policies and proliferation attempts and their implications for the current era. Indeed, it is more accurate to say that the book addresses the more specific question of “how American security guarantees can forestall nuclear proliferation” (155), as well as, implicitly, what the limits of those U.S. policies are.
Simply put, the U.S. is in a class of its own and the only case to which the theory is fully applicable. This does not make the book less interesting or important; the U.S. would be a fascinating case of a guarantor of extended deterrence even without the additional complicating factor of nuclear weapons. The U.S. is more secure than any other major power in history has been, and remote from the states to which it is extending deterrence. While extended deterrence of any kind is an inherently dubious proposition, it therefore might be particularly difficult for the United States to act as a guarantor. Arguably this is precisely why the physical presence of U.S. armed forces in or near allied territories is so important for U.S. alliance commitments. As Lanoszka notes (4), over half of the thirty or so states that considered nuclear weapons were aligned with the U.S., while only three states that had defensive alliances with the Soviet Union did the same (China, North Korea, Romania). Part of the explanation undoubtedly lies in the less than voluntary nature of the relationship of the Warsaw Pact countries to the Soviet Union, in contrast to that of the European and Asian allies to the United States. Yet, despite the considerable efforts of the U.S. to reassure them – whether through alliance commitments, economic assistance, political support, military aid, and conventional presence – its allies had good reasons to doubt the U.S. commitment and to fear the United States’ decoupling from their security.
Would guarantors located within a region fare better in terms of credibility were they to offer extended nuclear deterrence guarantees? For example, what if France or the UK offered extended deterrence to the rest of Europe? Would France need a forward deployed physical presence commensurate with that of the U.S., or would more minimal numbers, such as those currently part of NATO’s Enhanced Forward Presence (EFP), suffice? (Of course, strictly speaking, the concept of extended deterrence is incompatible with current French doctrine). French presidents have repeatedly stated that they would consider an attack on Europe as an attack on France’s vital interests. Does that constitute enough ‘skin in the game’ for France to be believable to other European states and to an adversary? During the Cold War, the French and British deterrents were intended to add additional uncertainty to the calculations of the Soviet Union. Did they add additional certainty to the calculations of NATO allies, despite their lack of explicit guarantees?
In a similar vein, somewhat under-examined in the book are the peer-to-peer dynamics within the alliances, such as those between France, Germany and the UK, and between Japan and South Korea. Did these add or subtract from the security felt by allies and the perceived need to acquire nuclear weapons? Was acquiring nuclear weapons a way to pull ahead from the regional pack? Lanoszka notes the example of West Germany’s outlook on the British and French nuclear programs (62), as well as those of others. However, how do these dynamics fit into the story told here? Is the U.S. more acceptable as an external guarantor of European or Asian security precisely because it is not a regional competitor to these states? While that might apply to the conventional balance of forces within the region, it seems less intuitive as a motivation for why regional states would accept the U.S. as an external guarantor of extended nuclear deterrence. It seems to me that these issues would also need to be addressed within a theory about alliance politics, specifically because the different dynamics between the U.S. and its allies within the multilateral NATO system and within the hub-and-spokes East Asian system.
The book’s contribution may therefore fall short of a generalizable theory about guarantors of extended nuclear deterrence, but I do agree that it goes a long way towards its ambition of offering a “more sophisticated view of how abandonment fears wax and wane,” unlike many accounts where “abandonment fears are constant, resulting either from the institutional design of the alliance or from idiosyncratic circumstances” (14). It is the examination of the variation over time that is most valuable, especially considering the current questions raised about long-term U.S. commitments. Moreover, Lanoszka makes an interesting distinction between policies where the U.S. is preventing attempts at proliferation and those where it tries to reverse them through various forms of political. It also prompts other questions. Are the other elements of policy that the U.S. as a guarantor might employ, such as exploiting economic or technological dependencies of allies on the U.S., still applicable outside of the Cold War context? Are many of the potential proliferators among allies of the U.S. still as dependent on the United States for their protection?
Unavoidably, despite the book’s structured approach, the argument becomes messier when the additional cases are considered. After all, non-proliferation is overdetermined as an outcome in most of the cases, and the alternative explanations in addition to U.S. alliance policies are non-exclusive (22). This may perhaps explain the focus on the U.S. and the conservative selection of its three major cases. Parsing which causes mattered most becomes difficult. For example, Lanoszka notes that Norway’s and Australia’s decisions to abandon their respective nuclear programs seem stories of domestic politics rather than U.S. alliance policies (140-143). He indeed emphasizes that the record of military alliances in curbing nuclear proliferation is less clear than some scholars suggest (147). If this is indeed the case, are we back to Dan Reiter’s conclusion that the conventional presence of the U.S. does not shape (non)proliferation among its allies? The book could have addressed why U.S. policies matter(ed) more for certain cases than for others, and specifically, why domestic politics can supersede both the perceived level of external threat and U.S. pressures in a few of them.
On a final note, the book concludes that the U.S. might not have the same clout over its allies as it did during the Cold War to prevent them from proliferating, though it may well continue to hold military and technological advantages over its adversaries (158). However, if one accepts the book’s argument, one will conclude that the U.S. in fact currently also has little leeway to change its current alliance policies. The U.S. will need much of the forces currently deployed to Europe and especially to Asia to remain in place in order to underline that it continues to have “skin in the game.” What does this mean regarding calls for U.S. grand strategies of restraint or offshore balancing? Are they doomed to fail, or, alternatively, are these strategies of retrenchment destined to lead to proliferation among current U.S. allies? Should we in fact even assume that the U.S. continues to have an overriding interest in nonproliferation, even though Lanoszka notes that those interests have been variable in the past (6)? One wonders what the author believes the worthwhile price is for this particular policy objective. That the book sparks several such follow-up questions, however, is proof of its analytical strengths and its relevance to policy.
This review was originally published on June 1st 2020 and is part of a larger article on the H-Diplo/ISSF Roundtable 11-17 on Lanoszka. Atomic Assurance: The Alliance Politics of Nuclear Proliferation.
 Full disclosure: In December 2015, as a workshop participant, I reviewed and commented upon parts of an early version of this book.
 Thomas C. Schelling, The Strategy of Conflict (Oxford: Oxford University Press, 1960), 195-199; J.D. Singer, “Inter-Nation Influence: A Formal Model.” American Political Science Review 57:2 (1963), 429-430. David A. Baldwin, “Power Analysis and World Politics,” World Politics 31:2 (1979), 188-190.
 Alexander Lanoszka, “Nuclear Proliferation and Nonproliferation among Soviet Allies,” Journal of Global Security Studies 3:2 (April 2018), 217-33.
 Glenn H. Snyder, Deterrence and Defense: Toward a Theory of National Security (Princeton: Princeton University Press, 1961), chap. 3.
 For a good example of the assumed automaticity prevalent in conventional thinking about U.S. grand strategy, see Kathleen Hicks, “Getting to Less: The Truth about Defense Spending,” Foreign Affairs (March/April 2020), 60.
 Glenn H. Snyder, Alliance Politics (Ithaca: Cornell University Press, 1997), 187-188.
 See also: Lawrence Freedman, The Evolution of Nuclear Strategy, 3rd ed., 2003 (New York: Palgrave Macmillan, 1981), 276.
 U.S. officials repeatedly expressed doubts that the U.S. would follow through on its guarantees. National Security Advisor for Richard Nixon, Henry Kissinger, at a private gathering of American and European strategies in Brussels in September 1979 said: “If my analysis is correct, we must face the fact that it is absurd to base the strategy of the West on the credibility of the threat of mutual suicide… and therefore I would say […] that our European allies should not keep asking us to multiply strategic assurances that we cannot possibly mean or if we do mean, we should not want to execute because if we do execute, we risk the destruction of civilization.” Cited in Earl C. Ravenal, “Counterforce and Alliance: The Ultimate Connection,” International Security 6:4 (1982), 37. Defense Secretary for John F. Kennedy and Lyndon B. Johnson, Robert McNamara, wrote that “in long private conversations with successive Presidents Kennedy and Johnson-I recommended, without qualification, that they never initiate, under any circumstances, the use of nuclear weapon.” Cited in David Garnham, “Extending Deterrence with German Nuclear Weapons,” International Security 10:1 (1985), 97. See also Reid Pauly’s analysis of the reticence of U.S. officials to escalate to the use of nuclear weapons during wargames: Reid BC Pauly, “Would US Leaders Push the Button? Wargames and the Sources of Nuclear Restraint,” International Security 43:2 (2018): 151-192.
 The most important thing about U.S. ground forces in Europe was “their nationality”. Freedman, The Evolution of Nuclear Strategy, 276.
 For example, Marc Trachtenberg made clear in his classic Constructed Peace how important the presence of American forces was to reassure Western Europeans – and specifically West Germans and the French – that the U.S. would not abandon them. Marc Trachtenberg, A Constructed Peace: The Making of the European Settlement, 1945-1963 (Princeton: Princeton University Press, 1999).
 Julian Barnes and Cooper, “Trump Discussed Pulling U.S. From NATO, Aides Say Amid New Concerns Over Russia,” The New York Times, 14 January 2019; Bert Thompson, Ulrich Kühn, and Tristan Volpe, “Tracking the German Nuclear Debate,” Carnegie Endowment for International Peace, 15 August 2018, https://carnegieendowment.org/2018/08/15/tracking-german-nuclear-debate-pub-72884. During the 2016 campaign, President Trump signaled a willingness to discuss proliferation to U.S. allies in Asia. Charlie Sykes, “Interview with Donald Trump” (620 WTMJ, 28 March 2016), https://soundcloud.com/620-wtmj/charlie-sykes-interviews-donald-trump; Editorial Board, “A Transcript of Donald Trump’s Meeting with The Washington Post Editorial Board,” Washington Post, 21 March 2016, https://www.washingtonpost.com/blogs/post-partisan/wp/2016/03/21/a-transcript-of-donald-trumps-meeting-with-the-washington-post-editorial-board/.
 Barry R. Posen, Restraint: A New Foundation for US Grand Strategy (Ithaca: Cornell University Press, 2014), 61; John J. Mearsheimer, Great Delusion: Liberal Dreams and International Realities (New Haven: Yale University Press, 2018), 232-233; Stephen M. Walt, The Hell of Good Intentions: America’s Foreign Policy Elite and the Decline of US Primacy (New York: Farrar, Straus and Giroux, 2018), xi.
 Vesna Danilovic, “The Sources of Threat Credibility in Extended Deterrence,” Journal of Conflict Resolution 45:3 (2001): 341-369.
 Bruno Tertrais, “Will Europe Get Its Own Bomb?,” The Washington Quarterly 42:2 (2019): 47-66.
 Jacques Chirac, “Speech by Mr. Jacques Chirac, President of the French Republic, during His Visit to The Strategic Air and Maritime Forces at Landivisiau / L’Ile Longue,” (19 January 2006), http://www.nuclearfiles.org/menu/key-issues/nuclear-weapons/issues/policy/french-nuclear-policy/PDFs/Chirac,%20Speech%20Delivered%20at%20the%20Strategic%20Air%20and%20Maritime%20Forces%20at%20Landivisiau.pdf; Francois Hollande, “President Hollande, Speech on Nuclear Deterrence, 19 February 2015,” http://www.nuclearfiles.org/menu/key-issues/nuclear-weapons/issues/policies/President-Hollande-Speech-on_a921.pdf.
 Bruno Tertrais notes that French officials emphasize that when the French Air Force participates in the air defense of the Baltic States, it does so as the air force of a nuclear power, and that they believe that Russia understands this. Tertrais, “Will Europe Get Its Own Bomb?”: 54.
 Robert J. Art, A Grand Strategy for America (Ithaca: Cornell University Press, 2013).
 Francis J. Gavin, “Strategies of Inhibition: US Grand Strategy, the Nuclear Revolution, and Nonproliferation,” International Security 40:1 (2015): 9-46; Gene Gerzhoy, “Alliance Coercion and Nuclear Restraint: How the United States Thwarted West Germany’s Nuclear Ambitions,” International Security 39:4 (2015): 91-129.
 Dan Reiter, “Security Commitments and Nuclear Proliferation,” Foreign Policy Analysis 10:1 (2014): 61-80.
 For example: Posen, Restraint; Walt, The Hell of Good Intentions; Mearsheimer, Great Delusion., as well as Christopher Layne, The Peace of Illusions: American Grand Strategy from 1940 to the Present (Ithaca: Cornell University Press, 2006); Andrew J. Bacevich, “Ending Endless War: A Pragmatic Military Strategy,” Foreign Affairs 95 (2016), 36; Stephen Wertheim, “How to End Endless War,” The New Republic, 22 March 2019, https://newrepublic.com/article/153239/end-endless-war-case-against-american-military-supremacy.