Allied with Constraints: U.S. Adaptive Integration of Nuclear-Constrained Allies

Introduction

NATO has long described itself as a nuclear alliance, but not all members participate in nuclear integration the same way. Some permanently host warheads or operate dual-capable aircraft or both, while others reject peacetime nuclear hardware altogether. Among the most resistant to peacetime nuclear basing were two Nordic allies, Norway and Denmark – strategically vital but constrained by domestic politics. The Cold War quest to fuse deterrence credibility with restraint on the Soviets drove the United States to regard the High North as “a gigantic Gibraltar” guarding the Atlantic bridge to Europe (Berdal, 1997c, p. 14; Egeland, 2025, p. 48). Since NATO’s founding in 1949, Washington’s strategic imagination revolved around three interests: denying the Soviet navy exits from the Kola Peninsula, securing forward positions from which nuclear forces could threaten the Soviet heartland, and anchoring American leadership within the Atlantic alliance (Tamnes, 1991, pp. 29–31).

Washington’s defense planning thus emphasized deeper integration with the Northern Flank. Yet, Norway and Denmark instituted self-imposed limits and screening mechanisms – a “balancing act” shaped by domestic antinuclear sentiment and risks of escalation of tension with the Soviets (Tamnes, 1987, pp. 67–71; Agger & Wolsgaard, 2006, p. 77; Petersen, 2012, p. 82; Holst, 1966; Holbraad, 1991). Taken together, allies’ strategic importance and political reluctance raise the question of how a patron manages defense relations with such allies in practice. The alliance management shapes how small states adjust intentions and capabilities (Braut-Hegghammer & Bowers, 2026).

Existing scholarship on nuclear alliances provides valuable insight but tends to focus on the more tangible, hardware contributions (Byun & Lee, 2021; Fuhrmann, 2018; Fuhrmann & Sechser, 2014a). Studies of reassurance and deterrence highlight how patrons respond to the dual dilemma of abandonment and entrapment (Morrow, 1994; Snyder, 1984), while others examine how small states hedge or leverage capabilities to secure more robust commitments (Buzan, 1983; Handel, 1990b; Vital, 1967). Important Nordic historical studies have shown in rich detail how Norway and Denmark balanced alliance integration with national reservation policies, and how U.S. strategy shaped the Northern Flank (Holbraad 1991; Holst, 1966; 1984; Skogrand & Tamnes, 2001; Tamnes, 1987; 1991; Villaume 1995). Taken together, these studies still leave room for further exploration of how patrons adapt the forms of integration within extended deterrence arrangements to accommodate the domestic political constraints of strategically vital allies. This points to the need for a closer examination of the patron–protégé relationship as an evolving process of adaptation, bargaining, and differentiated participation.

Thus, in this article, I examine how a nuclear patron manages operationally meaningful allied participation when protégés’ domestic nuclear policies diverge from the patron’s ideal expectations, yet protégés’ territory and cooperation remain central to the patron’s nuclear deterrence strategy. How, I ask, does the United States manage alliance integration over time with strategically vital but politically constrained allies? The inductive analysis centers on Denmark and Norway: longstanding U.S. allies whose geography is critical to Washington’s extended nuclear defense planning, but whose domestic politics have consistently opposed peacetime basing of nuclear weapons. I investigate, therefore, how the United States integrated these nuclear-reluctant but strategically important Nordic small states into NATO’s nuclear posture during key Cold War phases, drawing implications for the post-2022 context and largely for extended nuclear deterrence arrangements.

Across these phases, the United States largely maintained NATO’s nuclear posture through broader participation. In broad strokes, Washington responded to allied domestic nuclear resistance not by abandoning cooperation or coercing compliance, but by accommodating allied constraints and pursuing an adaptive strategy of differentiated integration – software integration. The term refers to operationally meaningful allied participation that sustains allied integration as an alternative to visible nuclear hardware roles while accommodating allied reservations. Rather than a substitution for unrealized basing plans, it functioned as a compensatory strategy, maintaining deterrence coherence of the alliance by deepening differentiated participation. Such participation served Washington’s geostrategic interests and NATO’s broader nuclear integration strategy – the incorporation of allied forces, territories, and operational practices into the alliance’s collective nuclear posture. Although frustrated by unrealized nuclear basing goals, the United States managed its Nordic allies – troublesome but influential small states – through tailored tools and trade-offs that sustained participation without breaching the allies’ domestic constraints or provoking adversaries. This illustrates how “alliances can advance diverse but compatible interests” and how a state “will judge the attractiveness of an alliance by comparing the benefits of the ally’s ability to advance its interests to the costs of advancing the ally’s interests” (Morrow, 1991, p. 905). The approach holds broader relevance for understanding the management of divergent allied interests.

Together, this article makes three main contributions to the study of alliances and extended deterrence. First, it provides a historical account of how the United States and Norway, and Denmark managed the tensions between nuclear integration within the extended nuclear deterrence arrangement and allied restrictions on peacetime nuclear basing across key phases of the Cold War, drawing on archival and secondary sources. By shifting the focus from Nordic reservation policies to Washington’s adaptation of its expectations over time, it shows how national caveats coexisted with the U.S. and NATO’s collective defense strategy. Second, showing how alternative forms of cooperation functioned collectively as operationally meaningful alternatives when nuclear hardware integration proved politically difficult, the article develops a descriptive typology of software integration. The typology identifies four domains of cooperation as interlinked components of a U.S. adaptive strategy of differentiated integration: intelligence and early warning; training, exercises, and consultation; contingency logistics and infrastructure; and institutional voice. These forms of participation sustained alliance integration despite the absence of peacetime nuclear basing. Third, the article situates these historical dynamics within contemporary debates on alliance management and extended deterrence under renewed tensions. It offers insights into how patrons and smaller allies continue to negotiate expectations, responsibilities, and political limits within evolving extended deterrence arrangements.

The article proceeds as follows. I first situate the study within existing scholarship. I then analyze evidence from Cold War phases: NATO’s founding (1949–1957), discussing early nuclear policy, U.S. expectations, and allied reservations; the shift from the doctrine of massive retaliation to flexible response (1961–1963), which redefined nuclear roles for small states; and the late Cold War (1980s), when renewed East–West tensions tested integration mechanisms. Based on this analysis, I develop a descriptive typology of allied software integration conceptualizing Washington’s modus vivendi with constrained allies. In conclusion, I summarize the findings and reflect on their implications for contemporary debates on alliance management, credibility, and extended deterrence under renewed alliance dynamics.

The Nuclear Question in Alliances

More formally pronounced during the Eisenhower administration (1953–1960), nuclear sharing “became the backbone of U.S. grand strategy in Western Europe and manifested in its most substantive form” (Byun & Lee, 2021, p. 71). Yet the nuclear question in NATO’s Northern Flank unfolded differently from what the United States had expected. Nuclear integration was complicated, shaped by the intersection of small-state behavior and U.S. expectations for allied integration. In this regard, Norway and Denmark offer analytically prominent cases for examining how non-nuclear states can be integrated into a nuclear alliance despite legal and political restrictions on hosting nuclear weapons – illustrating one form of U.S. nuclear defense strategy (Kristensen et al., 2023, p. 393).

While early scholarship portrayed small states as passive, overlooking how their nuclear choices shaped great-power interests, more recent contributions challenge this view. Unfolding this scholarship, Vital (1967) and Buzan (1991) laid the foundations for understanding the limited defense options available for small states. Vital (1967, p. 87) notes that small powers are “more vulnerable to pressure… more limited in respect of the political options open to them.” Others argue that small states can exploit great-power competition to enhance autonomy. Towards this end, Handel (1990b, pp. 45–46) observes that “weak states are by no means impotent … they learn to manipulate competition … and exert considerable influence” (see also Efremova, 2019, p. 104). Buzan (1983, p. 66) similarly argues that “strength as a state neither depends on, nor correlates with power,” citing Norway as an example. Handel (1990a, p. 72) further highlights how “the question of strategic importance for other states, especially the great powers,” shapes the prospects of weak states (emphasis in original).

Later work builds on this by suggesting that small states in sensitive regions may gain bargaining power precisely through vulnerability. Efremova (2019, p. 114) describes such states as “buffers,” whose proximity to adversaries makes their alignment strategically vital but politically fraught. These perspectives show that when small states are strategically important, yet vulnerable, great powers often exercise restraint, recognizing that alienating them costs more than enforcing compliance.

Alliance theory addresses related aspects. Snyder (1984) explains the “abandonment-entrapment” dilemma, where competing allied interests generate tension. He emphasizes that estimates of choice and tradeoffs in this dilemma involve weighing benefits, costs, risks, and relative dependence (Snyder, 1984, p. 471). Importantly, the degree of strategic interest – “an interest in keeping the ally’s power resources out of the opponent’s hands” – can be identified as the strongest factor driving Washington’s integration efforts with Nordic allies (Snyder, 1984, p. 473).

As an integration effort, the hardware integration strategy of the forward deployment of nuclear weapons is often considered a costly signal of resolve – an act of “project[ing] intentions” of deterrence to “persuade enemies or allies that one would fight abroad under circumstances of great risk and cost” (Schelling, 1966, p. 36; see also Trachtenberg, 1999; Fearon, 1997; Morrow, 1994; Fuhrmann & Sechser, 2014a; 2014b; Fuhrmann, 2018). Nuclear deployments are thus often framed as linchpins of extended deterrence and more credible sunk costs than alternative forms. This is challenged, however, by more recent work arguing that “placing nuclear weapons on an ally’s territory does much less to bolster extended deterrence than one might initially think” (Fuhrmann, 2018, p. 51). Generally, much of the literature assumes allies seek tighter nuclear coupling and that joining an alliance usually requires abandoning conflicting domestic policies (Morrow, 1993, p. 231; see also Morrow, 1999). By contrast, empirical studies of Denmark and Norway complicate these expectations, showing how they resisted peacetime nuclear basing while remaining embedded in NATO’s nuclear strategy.

Tamnes (1987, 1991) argues that Norway followed a policy of “integration and screening”: embracing alliance structures while maintaining autonomy through restrictions; Denmark did likewise (see also Villaume, 2008). As argued, many U.S–Norway collaborations amounted to “compensa[ting] for the peacetime absence of American military power” (Tamnes, 1991, p. 298). Villaume (1995, as cited in Villaume, 2008) portrays Denmark’s NATO posture as allied with reservations, arguing that “the Danish policy profile in NATO during the Cold War was characterized by more, and partly more far-reaching, reservations towards certain aspects of US and alliance policies than most other member nations, perhaps with the exception of like-minded Norway” (Villaume, 2008, p. 37). Thus, Denmark’s cooperation – excluding peacetime nuclear deployments and U.S. bases (except Greenland) – has been described as an “à la carte” NATO membership (Dörfer, 1986; see also Honkanen, 2002, p. 41). Research also shows how alliance dependence shapes small states’ contributions (Oma & Petersson, 2019). Overall, the behavior of small Nordic allies illustrates the layered, procedural modes of participation, shaped as much by domestic politics as by alliance structures.

Tamnes (1991, pp. 17–31, 295–303) shows how evolving U.S. geostrategic perspectives – “mental maps” encompassing continental and maritime strategies and a strategic nuclear perspective – shaped Washington’s policy toward the High North. Depending on the dominant perspective, Norway and Denmark shifted between being a strategic centerpiece and a peripheral flank. Importantly, when peacetime basing proved politically impossible, the United States often turned to flexible alternatives without overstepping Nordic red lines, thereby preserving strategic advantage while strengthening the Northern Flank for hemisphere defense, offensive strike, and Arctic strategies (Tamnes, 1991, p. 31).

Another strand of research focuses on hierarchy and patron–protégé bargaining. Lundestad (1986, p. 263) describes Western Europe’s alliance with the United States as an “empire by invitation,” emphasizing smaller states’ agency in shaping American presence (see also Tamnes, 1987, p. 74). Honkanen (2002, p. 16) distinguishes between agenda-setting and issue-specific resistance as modes of influence within NATO. These distinctions matter for cases like Norway and Denmark, which resisted peacetime nuclear deployments yet played vital roles in communications, intelligence, and logistics planning.

Recent studies reinforce this perspective. Lee (2023) and Gartzke et al. (2024) show that Washington uses strategic resources, including nuclear systems, not only for deterrence but also to maintain alliance cohesion and leadership. In this regard, the United States shows willingness to accommodate allied reticence so long as alliance functionality is preserved. This raises a key empirical question: when allies such as Norway and Denmark exclude peacetime warheads, what contributions are accepted as operationally meaningful?

Von Hlatky and Lambert-Deslandes (2024, p. 509) highlight the “changing architecture and narrative” of NATO’s nuclear sharing and extended deterrence, showing that the alliance’s nuclear deterrence posture increasingly rests on a wider set of allied “active political participation” – including but not limited to the hosting of warheads (Von Hlatky & Lambert-Deslandes, 2024, p. 513). This opens space for investigating allied integration below the threshold of nuclear basing – forms of differentiated integration – that can still provide operational value to nuclear strategy. Norway and Denmark exemplify this: despite prohibitions on the peacetime storage of warheads, both underpinned NATO strategy through infrastructure, early-warning radar, naval surveillance, and coordination. These quiet contributions challenge the assumption that deterrence credibility and deeper alliance integration rest primarily on nuclear hardware, and illustrate how the United States sustains alignment despite political constraints.

Taken together, the existing literature suggests that small states possess limited but meaningful room to maneuver within alliances, shaped by their strategic value, domestic constraints, and the broader balance of dependence between patron and protégé. Alliance theory highlights how this space is structured by trade-offs between abandonment fears and entrapment risks, while studies of Norway and Denmark show that states combine integration with reservation through layered, conditional forms of participation. However, the extent to which the geostrategic leverage and domestic politics of allied small states constrain patrons – and prompt adjustments in broader alliance strategies – remains underexplored. Existing literature pays less attention to how patrons reorient the integration of strategically vital yet politically constrained allies into sensitive alliance functions, particularly where allied nuclear constraints require alternatives to more visible forms of military integration. Addressing this gap, this article shows how the U.S. managed alliance integration through differentiated forms of cooperation and conceptualizes these patterns of adaptive integration.

Methodological Approach and Analytical Framework

This study employs a descriptive, inductive research design grounded in archival and historical evidence. It treats description as an independent mode of inference: a way to identify patterns, relationships, and empirical variation rather than merely a preliminary step toward causal explanation (Gerring, 2012). The aim is not to build a deterministic model of alliance behavior, but to clarify how the United States managed integration with strategically important yet politically constrained allies by tracing recurring patterns in U.S.–Nordic nuclear relations. This approach follows the view that causal explanation first requires identifying the relevant empirical characteristics of the phenomenon under study (King et al., 1994, p. 34), and that historically grounded case studies can reconstruct decision sequences, institutional constraints, and strategic choices often obscured in broader accounts (González-Ocantos, 2020; Ruffa, 2020).

Within this framework, the article develops a descriptive typology – a classificatory tool that organizes empirical observations according to a common principle (see Gerring, 2012). The typology emerges inductively from the historical analysis of U.S., Norwegian, and Danish interactions within NATO and organizes patterns of differentiated integration into four domains. These domains crystallize the negotiated exchange, in which alternative forms of cooperation were traded for peacetime nuclear basing. The typology thus aims to clarify historical patterns of alliance management while offering a conceptual framework for potential comparative analysis of other extended deterrence relationships.

The study draws on Cold War archival evidence (see Appendix A) and secondary literature on U.S., NATO and Norwegian, and Danish security relations. Declassified records and diplomatic correspondence reveal how U.S. policymakers assessed Nordic nuclear reluctance, adjusted expectations, and treated differentiated participation as strategically useful. Within the scope of this study, it does not differentiate among the internal debates within the United States government, the armed services, and the intelligence community, and refers to the broader patterns of policy.

Norway and Denmark are analytically valuable cases as both rejected peacetime nuclear basing while remaining deeply integrated into NATO’s broader nuclear strategy. The study focuses on three prominent phases – 1948–1957, 1961–1963, and the 1980s – when nuclear issues were especially contentious, U.S. policy shifted, and Nordic participation became particularly salient. This temporal focus allows the article to examine the strategic decisions and alliance adjustments at key moments of the Cold War. With nuclear deterrence and forward basing re-entering Nordic debates, this study’s implications are of contemporary relevance and may inform today’s management of allied expectations and demands within the increasingly volatile alliance order.

Phase I: NATO’s Early Years: U.S. Early Expectations and Allied Responses (1949–1957)

The formative years of NATO posed a challenge for U.S. alliance strategy. As Washington sought credible forward nuclear deterrence against the Soviet Union, it encountered hesitation from smaller allies who were strategically positioned. Particularly, Norway and Denmark “became members of NATO on special conditions, which Oslo framed, and Copenhagen seconded. Notable among these was one which reserved the stationing of foreign bases in peacetime” (Holst, 1984, p. 197; see also Villaume, 2008, p. 40). The reservation extended to the hosting of nuclear weapons and grew stronger with the formalization of NATO’s nuclear strategy (NATO, 1954). Reluctance stemmed from domestic anti-nuclear sentiment, concerns of escalation of tension given the proximity to the USSR, and fears of entrapment (Tamnes, 1987, p. 73; Villaume, 2008, p. 40; see also Sukin, 2020).

From early on, the United States recognized the geostrategic importance of the High North to its defense strategy (Bykova et al., 2025, pp. 135–143). Norway guarded Soviet naval access to the Atlantic, and Denmark’s control of the Kattegat Sea area locked the Baltic fleet behind a chokepoint (Berdal, 1997a, p. 14; Tamnes, 1991, pp. 71, 74–79; Saxi, 2010, p. 22). Washington prioritized dispersal bases for Strategic Air Command (SAC), early-warning infrastructure, and assured wartime access (Tamnes, 1991, pp. 74–79). Nordic leaders, however, feared becoming a nuclear tripwire: exposed and unable to control escalation.

Even though both Norway and Denmark looked to the West, their nuclear conduct did not align with Washington’s ideal nuclear defense planning. Norway’s 1949 base policy and Prime Minister Gerhardsen’s 1957 declaration barred peacetime nuclear weapons (Tamnes, 1991, p. 164; Cameron, 2024). Denmark followed with its 1957 ban on peacetime nuclear basing (Holbraad, 1991, p. 134; Doeser, 2011, p. 227). Norway pledged it “will not open bases for the armed forces of foreign countries unless attacked or threatened with aggression” (Riste, 2001, p. 203), reflecting cross-party consensus on neutrality and sovereignty domestically, and signaling restraint towards Moscow internationally. Towards Moscow, as scholars argue, Norway pursued a balance between “deterrence and reassurance” – deterrence with NATO membership and reassurance with peacetime basing reservations (Cameron, 2024; Cameron & Bruusgaard, 2024).

U.S. leaders publicly accommodated Norwegian reservations. Both Supreme Allied Commander Europe (SACEUR) General Eisenhower and Chief Commander of Northern Command Admiral Brind “emphasized that the U.S. requirements would not violate Norway’s base policy” (Tamnes, 1991, p. 71) and were “willing to meet Norwegian demands” (Tamnes, 1987, p. 68). While Oslo reiterated its base policy, Washington mostly acquiesced with occasional exceptions. When seeking base rights for tactical aircraft – SAC access at Sola and Gardermoen – Washington’s persistence created “a most awkward problem” (Tamnes, 1991, p. 72; Berdal, 1997b, pp. 33–35). Following lengthy negotiations, a 1952 agreement allowed Washington the use of Sola and Gardermoen under peacetime basing restrictions and limits on stockpiling and personnel (Tamnes, 1987; 1991, pp. 73–74).

Short of nonnegotiable peacetime nuclear basing, the United States encouraged deepening cooperation through other domains. Norway hosted Allied Forces Northern Europe (AFNORTH) headquarters (Riste, 2001, p. 212; Palmer, 2024, p. 82), charted gaps in radar coverage along polar approaches, and expanded signals intelligence (SIGINT) under the 1952 NORUSA agreement (Riste, 2001, pp. 217–225; Tamnes, 1991, p. 76). Washington sweetened the deal with “massive amounts of arms and equipment … through the U.S. Military Assistance Program” (MAP) and substantial NATO infrastructure funding (Riste, 2001, p. 213).

Oslo gradually deepened its participation within Washington’s concept of “integrated defense,” localizing it as “coordinated defense” (Riste, 2001, p. 207). It followed a dual strategy of integration and screening, participating in the execution of U.S. and NATO strategy in the High North while retaining national control over peacetime foreign presence (Tamnes, 1987; 1991). The balance between the two shifted with geopolitical developments. While the Soviet build-up and the Korean War deepened Norwegian integration, particularly through joint exercises, tough U.S. demands resulted in screening measures (Tamnes, 1987, pp. 72, 87; Riste, 2001, pp. 210–211).

Generally, although Washington sought closer integration to advance its geostrategic priorities, it acknowledged Norwegian reservations. As Tamnes (1991, p. 164) noted, “when it came to nuclear weapons in Norway, the Americans clearly hoped for a responsive Norwegian attitude … used various means to convince the Norwegians, but this never amounted to pressure.” For example, in cases like the Nike and Honest John missile systems, the United States “recognized the political importance of satisfying the Norwegians with non-nuclear ammunition” (Tamnes, 1991, p. 164).

Denmark followed a similar trajectory of supporting NATO while cautious on foreign nuclear basing but with distinct domestic politics. Some parties favored the Scandinavian Defense Union, and leaders feared provoking Moscow – “an immediate excuse to occupy at least parts of Danish territory” and facing backlash from anti-nuclear constituencies (Villaume, 2008, p. 39; Agger & Wolsgaard, 2006). Danish skepticism surfaced at NATO’s Military Committee in November 1949, when Defense Minister Rasmus Hansen sought to delete explicit references to nuclear weapons from NATO’s first military undertaking – “prompt delivery of the atomic bomb” (Agger & Wolsgaard, 2006, p. 70). General Bradley resisted, but U.S. diplomats accommodated Danish concerns by softening the language to stress using “all means” without naming the bomb. Further, a 1952 U.S. offer to deploy permanent squadrons – U.S. Air Wings to Denmark and nuclearization of Danish forces – was shelved in 1953 amid public opposition evident in Gallup polling (Agger & Wolsgaard, 2006, p. 79; Villaume, 2008, p. 40).

Military aid bridged the differences to some degree. U.S. “deliveries of equipment to Denmark” totaled $353 million by 1956 (U.S. Department of State, 1957a, p. 514). Eventually, in the late 1950s, Denmark accepted the Nike missile systems “in principle”, but “not least because of considerable pressure,” and the prime minister stressed that it “would have declined a possible U.S. offer to store nuclear warheads” (Agger & Wolsgaard, 2006, p. 80). Denmark trained personnel in nuclear weapons operations, and prepared storage facilities for nuclear ammunition to send “positive Danish signals [to Washington and NATO] on the nuclear question,” without implying any commitment to peacetime nuclear hosting (Agger & Wolsgaard, 2006, pp. 81–82).

Greenland, a semi-autonomous, constitutionally Danish territory, became central to U.S. polar strategy (Bykova et al., 2025; Petersen, 2011). The 1951 U.S.–Danish defense agreement ensured access to Thule air base and allowed strategic expansion without parliamentary scrutiny (Holst, 1984, p. 199; Villaume, 2008, pp. 40, 143; U.S. Department of State, 1957a, p. 515; National Security Archive, 2025a; Agger & Wolsgaard, 2006). When Prime Minister Hansen tacitly approved the deployment of U.S. nuclear weapons in Greenland, he initiated what historian Thorsten Borring Olesen described as Denmark’s “double standard” nuclear policy. Publicly, Hansen reaffirmed in May 1957 that Denmark would not receive nuclear weapons “under the present conditions,” yet Copenhagen treated Greenland differently – quietly accommodating U.S. policy goals there to maintain stable relations with Washington while avoiding domestic backlash and Soviet pressure (National Security Archive, 2025a, p. 9; Ackren, 2019). However, after the 1968 B52 crash, Denmark ended its “double standard,” extending its non-nuclear policy to Greenland and its airspace (National Security Archive, 2025a, 2025b).

Strategically, the general alignment of Danish and U.S. interests diverged on certain aspects (Agger & Wolsgaard, 2006, pp. 70–71). Washington believed equipping local forces with nuclear weapons would strengthen deterrence and defense, but if deterrence failed, Copenhagen wanted to avoid escalation into an all-out nuclear war (Agger & Wolsgaard, 2006, pp. 77–78). As Holst (1984, p. 208) observed, “Denmark do not permit the stationing of Allied troops on their territories, but they insist that Allied maneuvers are necessary to underwrite deterrence.”

By 1952, the United States had secured much of what it needed from the Nordics: airfields, fuel depots, SIGINT sites at Vardø and Kirkenes (Riste, 2001, pp. 217–219), and B-36-capable runways at Thule. Both governments joined NATO’s first Northern Flank exercise – without a single nuclear weapon north of Hamburg.¹ Yet risks remained: the Joint Chiefs doubted rapid reinforcement capability; Oslo feared deterrence gaps in Finnmark; and Copenhagen worried about playing a “gap-filler” role without direct deterrence (Agger & Wolsgaard, 2006; Egeland, 2025).

Against this backdrop, Washington sought to deepen deterrence despite accepting Nordic restrictions. Under the doctrine of massive retaliation, Secretary of State Dulles’s 1953 “policy of candor” heightened anxiety in Oslo (Egeland, 2025, p. 50; Agger & Wolsgaard, 2006, pp. 72–73; Tamnes, 1991, pp. 92–96). Rather than normalizing nuclear weapons, U.S. messaging often reinforced fears that tactical warheads near Finnmark would invite attack rather than deter them (Egeland, 2025, pp. 52–55; Cameron, 2024, p. 369). These tensions foreshadowed later struggles between alliance expectations and domestic political constraints.

Even so, the record of this phase demonstrates that integration and cohesion endured through pragmatic adaptation. Rather than coercing or abandoning its Nordic allies, Washington accommodated peacetime nuclear basing constraints while deepening cooperation in other domains – particularly intelligence access and logistical readiness. For Norway and Denmark, this preserved political discretion while sustaining meaningful contributions to NATO’s deterrence posture. By decade’s end, Washington concluded that “it would be counter-productive at this time to attempt [to] pressure Danes to a decision to accept atomic weapons in Denmark” (U.S. Department of State, 1957b, 528, para. 437), a position equally extended to Norway.

In retrospect, this period set in motion a pattern of integration with differentiated strategic cooperation that facilitated Washington’s and NATO’s nuclear posture despite allied nuclear reservations. Although Norway and Denmark both rejected visible hardware nuclear arrangements, “allied exercises, and valuable intelligence gathering activities … were, however, welcomed and supported by Oslo and Copenhagen” (Petersson & Lunde Saxi, 2013, p. 765) – an indication they sought to reinforce NATO deterrence. A compromise between strategic objectives and allied constraints, the early U.S. maneuvers signaled a turn towards a less conspicuous, politically manageable alignment, enabling reluctant but strategically important allies to contribute without crossing their domestic red lines. While the contours later evolved, the foundational logic of software integration was set early in the Cold War.

Phase II: From Massive Retaliation to Flexible Response (1961–1963)

President Kennedy’s inauguration in January 1961 coincided with two developments that unsettled the fragile equilibrium forged in the 1950s. First, the Soviet Union’s rapid build-up of intermediate- and long-range missile forces, including deployments on the Kola Peninsula and in the Baltic region, convinced NATO planners that the Northern Flank might receive only minutes of warning in a crisis. Second, the Berlin crisis and Laos case exposed the limits of Eisenhower’s massive retaliation doctrine, heightening allied fears that Washington might either escalate too quickly or hesitate altogether (U.S. Department of State, 2025). President Kennedy and Secretary of Defense Robert McNamara responded with the doctrine of flexible response, a graduated strategy that combined conventional forces and forward deployed nuclear weapons to signal resolve and enhance deterrence against expanding Soviet capabilities (Tamnes, 1987, pp. 84–86; 1991, pp. 185–213; Riste, 2001, p. 214). Yet, as reported:

Washington and the Nordic capitals thus had to renegotiate the 1950s tacit bargain on differentiated integration, as peacetime nuclear deployments were still deemed untenable.

Norway accepted U.S.-supplied Nike and Honest John systems, which U.S. planners considered effective only with nuclear warheads (Tamnes, 1991, pp. 161–163). Nevertheless, a parliamentary motion of 1961, confirmed by cabinet in a white paper the same year, declared that nuclear weapons should not be placed on Norwegian territory. From 1961, Oslo withdrew from Support of Nuclear Operations with Conventional Air Tactics (SNOWCAT) exercises, dismantled most contingency preparations for wartime reception of U.S. warheads, and phased out the missile batteries. Both Nike and Honest John systems left service in 1965 without ever receiving nuclear ammunition (Egeland, 2025, p. 55; Skogrand & Tamnes, 2001, pp. 232–255; Tamnes, 1991, p. 162).

Washington found this frustrating but adjusted its expectations. After meetings in Washington, Defense Minister Harlem reported: “US approves GON [Government of Norway] defense policy, including GON views on nuclear weapons … There can no longer be any doubt that Americans really mean this … They were really in agreement, not merely accepting our viewpoint” (U.S. Department of State, 1963c, pp. 1–2). In parallel, President Kennedy acknowledged that “Norway occupy an important strategic area [and] the difficulty Norway had in meeting all its commitments to NATO and to its own people” (U.S. Department of State, 1963a, p. 3).

Coercing Oslo on nuclear hardware risked other geostrategic advantages, so Washington channeled efforts into the “intelligence-integration” track, expanding the 1954 NORUSA agreement with new funding and equipment. Norwegian intelligence sites at Vardø, Kirkenes, and Fauske became indispensable for tracking Soviet missile tests and submarine patrols (see Appendix B). Cooperating with Washington, the Norwegian Intelligence Service added listening pods at Barents Sea stations while retaining peacetime control (Riste, 2001, p. 217; 1999). The bargain suited both sides: Washington gained early warning without overstepping the base policy, while Oslo framed cooperation as nationally run and defensive – difficult for Moscow to contest and sufficiently discreet to defuse domestic critics.

Though U.S. envoys, in general, complained that “NATO defense has been handicapped by … refusal to accept the presence of U.S.-controlled nuclear warheads” (U.S. National Security Council, 1960, p. 675), Washington continued extensive aid “primarily directed towards … equipping Norwegian forces with advanced aircraft and missile systems” (U.S. National Security Council, 1960, p. 685). Under the Mutual Defense Assistance Program (MDAP) and MAP, Norway received “thousands of American tanks and artillery pieces … aircraft, helicopters, and … naval vessels free of charge” (Egeland, 2025, p. 63; Gjeseth, 2014).

Denmark entered the 1960s with a similar but more flexible policy. Two Social Democratic reservations – the 1953 ban on permanent allied forces and the 1957 prohibition on nuclear weapons – remained, but Copenhagen phrased its stance as “not under the present conditions,” leaving room for adjustment (National Security Archive, 2025a; Agger & Wolsgaard, 2006, p. 80; Petersen, 2012, p. 297). Foreign Minister Jens-Otto Krag told parliament the policy must “remain as flexible as possible and could not appear final” (Agger & Wolsgaard, 2006, p. 81). While managing public restraint, the government quietly authorized infrastructure for wartime reception of warheads, reassuring Washington and NATO. The United States reinforced the bargain, with aid and integrating Denmark into advanced missile systems such as Nike, Hawk, Honest John, and Sidewinder, but with “no major changes projected in the force structure or mission of the Danish forces,” accommodating Danish reservations (U.S. National Security Council, 1960, p. 686).

Nevertheless, Washington and SACEUR periodically pressed for clarification and were not fully satisfied with Denmark’s integration. Washington urged Defense Minister Hansen that it was “Denmark’s turn to augment its contribution to NATO build-up” (U.S. Department of State, 1961b, p. 2). Krag personally agreed Denmark could do more and pressed for deeper integration (U.S. Department of State, 1961c, p. 1), consistent with SACEUR recommendations in the Plan of Action–Supreme Headquarters Allied Powers Europe (SHAPE) 188/61 (NATO, 1961). Yet Ambassador William McCormick Blair Jr., mindful of constraints, stressed U.S. efforts ultimately depended on “what Denmark would do itself” (U.S. Department of State, 1961c, pp. 1–2).

The pressure remained subtle for two reasons. First, Greenland’s Thule Air Base hosted early-warning radars vital to the U.S. missile defense system (Villaume, 2008, p. 52; National Security Archive, 2025a), and Washington valued these assets more than visible warheads in Jutland (U.S. Department of State, 1957a, p. 515; Tamnes, 1991, pp. 72–74). Second, Norway’s identical ban gave Denmark diplomatic cover (Agger & Wolsgaard, 2006). As Dean Rusk observed, “despite the relatively small role it plays in Europe, Denmark is a staunch supporter of the West, and it has made a major contribution to North American defense in making Greenland available to United States military services” (U.S. Department of State, 1961a, p. 1).

The early 1960s bargaining record shows that rising threats pushed Washington toward tighter coupling, while Nordic domestic constraints sustained differentiated integration. Norway traded basing rights mostly for intelligence and consultation; Denmark leveraged Greenland and selective infrastructure to keep warheads out of Jutland while lowering its defense bill. The United States escalated expectations – from the zero-presence doctrine to contingency planning – but paired each step with offsets tailored to local politics. As Riste (2001, p. 225) notes, “towards the Americans, Norway’s willingness to cooperate doubtlessly served to counteract allied impressions of Norway as a reluctant ally, considering her many self-imposed restraints, against becoming fully integrated into allied military activities” and “low-tension” goals (see Holst, 1984, p. 199; Tamnes, 1991, p. 86). When the Nordics declined certain integration, the United States even floated alternatives (U.S. Department of State, 1961f).

Contributing to other forms of integration enabled the Nordics to voice even stronger opposition to nuclear weapons. Danish Prime Minister Kampmann “emphatically restated” opposition to accepting atomic weapons – “one of radical liberal leadership conditions for acceptance joint command” (U.S. Department of State, 1961d, p. 2). The U.S. accommodated – “we do not think the U.S. should intervene bilaterally at this time with Danes to urge their acceptance of atomic weapons or atomic training for their forces” (U.S. Department of State, 1961e, p. 1). Given the “Danish public policy of opposition to atomic weapons for Danish forces,” such initiatives “should be taken by [the] Danish Government itself” (U.S. Department of State, 1961e, p. 1).

Nonetheless, Washington’s attitude had its shifts. The Soviet threat was intensifying – “Soviet domination of Scandinavia would enable the USSR to deploy forces further to the West … increase the threat to the Western Hemisphere… threaten operations in the North Atlantic, and… form a protective shield against sea or air attack from the Northwest” (U.S. National Security Council, 1960, p. 674). U.S. policy aimed to “encourage the Scandinavian countries to support a firm Western political and military position as a deterrent to Soviet Bloc aggression and as a prerequisite to the negotiation of an acceptable and stable modus vivendi” (U.S. National Security Council, 1960, p. 678). In general, as mentioned in SHAPE 188/1, the U.S. noted, “the efforts of Norway and Denmark are appreciated but fall short of the desired goals … particularly in the absence of nuclear weapons, will involve risk … effectiveness from the limited forces available must be expedited” (NATO, 1961, p. 2).

American frustration persisted over broader European NATO inaction – “During 1962 we went to our allies in good faith and asked them to come up with suggestions concerning the possible sharing of nuclear responsibilities. Nothing happened” (U.S. Department of State, 1963b, p. 3). U.S. reports complained about “no consensus regarding the problems confronting NATO,” citing divisions over strategy, Russian intentions, and nuclear policy (U.S. Office of International Security Affairs, 1962, p. 4). The proposal on the Multilateral Force (MLF) crystallized these differences. While Washington framed the MLF as a symbol of unity – “a European collective deterrent [to] increase the deterrence to Soviet nuclear or non-nuclear aggression” (U.S. Office of International Security Affairs, 1962, p. 8), Norwegian Foreign Minister Lange feared that the United States was overly urging its European allies to accept the MLF (U.S. Department of State, 1963b, p. 3).

By the mid-1960s, Washington recognized the limits of persuasion. It tempered expectations, accepted Nordic reservations, and increasingly relied on software integration – intelligence, infrastructure, and consultation to preserve deterrence cohesion within political constraints.

Phase III: Late Cold War (1980s)

By the early 1980s,² NATO’s nuclear posture faced renewed challenges as Soviet missile deployments intensified, and “new perceptions of threat meant that the High North was about to attain a far more prominent role in the … geostrategic perspective” (Tamnes, 1991, p. 229). Although new Ballistic Missile Submarines (SSBNs) were folded into the strategic concept, the Kola bases could reshape the broader maritime strategy in the Norwegian Sea (Tamnes, 1991, p. 229). As the Reagan administration pressed nuclear modernization and firmer integration, both Norway and Denmark showed renewed ambivalence. For Washington, maintaining a coherent nuclear posture implied deepening alliance integration; for Oslo and Copenhagen, domestic opposition to peacetime nuclear deployment similarly remained strong but they responded differently. Denmark responded through visible parliamentary resistance, while Norway responded through discreet alignment.

Norway entered the decade amid surging anti-nuclear activism. Extending hopes for détente since the early ‘70s and “low-tension” sentiments (Tamnes, 1987, p. 87), the “No to Nuclear Weapons” campaign mobilized about 100,000 members, and a petition for a Nordic nuclear-weapon-free zone gathered over 500,000 signatures – around one-eighth of the population (Riste, 2001, p. 230). Although the Labor government supported NATO’s 1979 dual-track decision, it faced deep internal fractures. Parliamentarians and party members challenged the deployments of Intermediate-Range Nuclear Forces (INF), and the movement for a Nordic nuclear-free zone gained traction (Holst, 1984, pp. 214–218; Tamnes, 1983, pp. 84–86; 1987, p. 92; Cameron, 2024, pp. 378–381). Moral resistance within the Labor movement and religious communities shaped this cautious posture (Egeland, 2025, p. 60).

Washington responded firmly, warning of “threats to suspend plans for reinforcements to Norway if such a zone was established” (Riste, 2001, p. 231). Norwegian leaders backed off, recognizing the strategic cost of any escalation. Ties were tested again in 1986 when Defense Minister J.J. Holst withheld Norway’s endorsement of a NATO communiqué on the Strategic Defense Initiative (SDI), and “joined as a footnote country,” again prompting “Americans [to] react sharply” (Riste, 2001, p. 231). Washington suspended a bilateral study group and froze funding for Norwegian air defense modernization. This shows that U.S. accommodation had its limits and, within its boundaries, responded firmly when necessary.

Despite tensions, Norway’s strategic role deepened. The Soviet bastion strategy – anchoring SSBNs in the Barents Sea – made the Norwegian Sea central for Washington’s maritime surveillance and Anti-Submarine Warfare (ASW) (NATO, 1969, pp. 383–384; Kjellén, 2022, pp. 39–44; Tamnes, 1987, p. 85; 1991, p. 229). In 1981, Norway signed a bilateral agreement allowing prepositioning of U.S. Marine Corps equipment, later in 1982, incorporated into NATO’s Rapid Reinforcement Plan (Tamnes, 2024, p. 280; Cameron, 2024). Norway also expanded participation in NATO exercises involving dual-capable aircraft but with continued peacetime basing constraints and checks on exercises “in Finnmark county bordering the Soviet Union” (Cameron, 2024, p. 369; Tamnes, 2024). For Washington, these contributions sustained operational readiness and reinforced deterrence without crossing Norway’s nuclear red lines. In general, Norway’s dissent remained largely contained within party and executive circles. Norwegian leaders generally framed NATO participation as compatible with restraint, avoiding public rupture (Holm, 1989, p. 182). Even amid internal debate, the government favored negotiation over confrontation, preserving Norway’s image as “semi-allied” – a “loyal dissenter” while maintaining valuable roles in intelligence, planning, and early warning (Tamnes, 1991; see also Riste, 2001).

Denmark’s trajectory diverged. From 1982 to 1988, the “footnote policy” saw parliament, the Folketing, attach critical annotations to NATO communiqués (Petersen, 2012). Holm (1989) characterizes this as a “democratic revolt,” with the legislature exerting direct control over foreign and security policy.³ Footnotes rejected President Reagan’s SDI, questioned INF deployments, and endorsed a Nordic nuclear-free zone – calling for postponement of NATO’s tactical nuclear missiles deployment in Western Europe, a nuclear freeze in the West and East, and a nuclear tests ban (Villaume, 2008, p. 44). The United States was “dead against the zone idea” (Petersen, 2012, p. 305), and “Denmark’s performance did not escape US criticism” (Petersen, 2012, p. 298).

Frustrated yet cautious, Washington countered any decoupling given the geostrategic advantages. Secretary of State Shultz reportedly told Danish officials: “If all Europeans were like you, there would be no NATO” (Petersen, 2012, p. 306). Still, given Denmark’s control over the Baltic gateway and the indispensable Thule radar base in Greenland, Washington refrained from overt coercion or actions that might jeopardize the relationship. Thule’s upgrade continued with tacit approval from Copenhagen, which treated Greenland as a “grey zone” outside mainland nuclear constraints (Petersen, 2012, p. 298). U.S. planners also underscored the centrality of Denmark’s merchant marine and logistics infrastructure as critical to NATO reinforcement (Bjoernsson, 2023, p. 221).

Public opinion heavily shaped Danish policy, and leaders responded to electoral pressures and coalition dynamics (Doeser, 2011, pp. 227–228). Prime Minister Jørgensen (1972–1973, 1975–1982) and Foreign Policy Spokesman Budtz (1979–1987) steered the debate in an anti-nuclear direction. Jørgensen declared, “We are members of NATO, but I am absolutely against nuclear weapons” (Petersen, 2012, p. 299). These moral convictions, driven by electoral politics and institutionalized dissent, prompted the United States to abandon nuclear deployment goals and pursue and enhance secondary forms of cooperation that were mutually compatible.

Thus, software integration, which underscored differentiated participation, further developed as an intersection of what the allies could offer and what the United States accepted as operationally meaningful contributions. Norway leveraged its reputation as a dependable ally through intelligence sharing, prepositioning, and rapid reinforcement planning (Tamnes, 2024, pp. 277, 280, 284). Denmark, though often troublesome, remained vital through infrastructure support, civil-military coordination, and especially through Greenland’s strategic value (Villaume, 2008, p. 51). In both cases, the visible military presence remained minimal, while alliance integration progressed through procedural and software contributions.

The two Nordic cases contrast with Washington’s approaches elsewhere. In the Philippines, nuclear weapons were deployed to Clark and Subic without consulting the government (U.S. Department of State, 1969) and blindsiding senior officers (Magallona, 1991, pp. 31–35). The covertness triggered “tension and resentment … evoking concerns over sovereignty and autonomy, leading to periodic frictions in the alliance” (Suporn, 2025, p. 31), leaving the country “a cog in the U.S. nuclear strategy” (Magallona, 1991, p. 35). In Canada, the only partial disclosure of deployment of Bomarc missiles armed with nuclear warheads and dual-capable CF-104 aircraft triggered strong debate (Bothwell, 2007; Maloney, 2007). In Iceland, while no nuclear weapons were deployed, declassified records reveal debate over secret deployments; Ambassador Thompson warned Reykjavik might quit NATO if exposed, triggering a “dramatic row” (National Security Archive, 2016). In comparison, in the cases of Denmark and Norway, the United States adopted differentiated integration when basing proved untenable, maintaining consensus and legitimacy while securing meaningful contributions without triggering alliance tension – a demonstration of the approach’s effectiveness.

Historical relations with the two Nordic allies show a consistent pattern: when U.S. expectations conflicted with Nordic prohibitions, Washington adapted through differentiated software integration. Cold War empirical evidence reveals how this U.S. approach became an enduring modus vivendi of U.S.–Nordic nuclear relations.

Modus Vivendi – An Adaptive Strategy of Differentiated Integration

The U.S. approach to constrained allies can be understood as a modus vivendi – a practical accommodation in which allied roles in American defense planning were shaped by broader strategic imperatives (Riste, 2001, p. 200). Drawing on Cold War records, I develop a descriptive typology of diplomatic and security practices to show how Washington pursued nuclear alignment with two politically constrained yet strategically vital allies. The record reveals an approach of software integration – a differentiated form of alliance integration – across four recurring domains: (1) intelligence and early warning, (2) training, exercises, and consultations, (3) contingency logistics and infrastructure, and (4) institutional voice. The approach allowed Washington to integrate Denmark and Norway into NATO’s nuclear posture, ensuring meaningful allied participation towards achieving its geostrategic goals while accommodating allies’ peacetime nuclear constraints.

By identifying recurring domains of participation, the typology clarifies the specific roles that Norway and Denmark played within NATO’s nuclear posture. This adaptive integration framework may also be applicable beyond the two Nordic cases – other alliance contexts characterized by uneven participation and political restrictions. The findings largely suggest that, rather than viewing nuclear hardware roles as the primary means of alliance integration, there exists an alternative pathway through differentiated forms of cooperation that sustain deterrence while accommodating allied constraints. When patron expectations exceed what protégés can accommodate within political or strategic priorities, such alternative forms of participation allow allies to remain integrated without necessarily straying from their priorities mitigating alliance tension.

Conclusion

The United States and its Nordic allies navigated uncharted waters, arriving at a modus vivendi through differentiated integration, showing how allies adapt to tensions between strategic dependence, domestic constraints, and evolving deterrence requirements. As set out in prominent Nordic scholarship, “Norway’s and Denmark’s ban on nuclear weapons … generated much political and public debate but did not prevent the two countries from approving NATO’s nuclear policy and being an integral part of it” (Tamnes, 2024, p. 281). Through a historically grounded analysis of U.S. and NATO–Nordic relations, this article shows how the United States integrated Norway and Denmark – two strategically vital but politically constrained allies – into its broader nuclear strategy across the Cold War. Rather than coercing the allies to comply against their reservations or abandoning them, Washington pursued a compensatory strategy of software integration across four domains: intelligence and early warning; training, exercises, and consultations; contingency logistics and infrastructure; and institutional voice. Bridging nuclear and conventional spheres, this adaptive strategy of integration allowed the United States to secure operationally meaningful allied contributions when nuclear hardware integration proved politically untenable, sustaining deterrence and alliance cohesion despite allies’ constraints.

Post–Cold War variations in geopolitics, leadership, strategic and military culture (Saxi, 2010) did not alter the fundamental logic. Norway and Denmark have retained their prohibitions yet remain integral to U.S. and NATO’s strategic planning – tied to NATO’s nuclear posture through software-based contributions. Thus, the logic of software integration largely endures, but under sharper and more conditional expectations. Whereas Cold War pressures were often managed discreetly, contemporary alliance politics increasingly reflect a more explicit and, at times, transactional approach to burden-shifting and commitment. NATO’s renewed focus on territorial defense and the Arctic has sharpened its expectations and demands. As NATO’s Secretary General Mark Rutte recently reiterated, “NATO is increasing focus on the High North through improved situational awareness, reinforcement, improved capabilities, revised command and control arrangements, increased exercises and training” (NATO, 2025a). This introduces a new layer of uncertainty – in addition to the risk of abandonment, allies must now navigate fluctuating commitments and rising demands for burden-sharing (Blankenship, 2024).

Relatedly, amid growing concerns over trust, reliability, and conditional U.S. commitments, recent scholarship highlights shifting protégé behavior and renewed debates over a “Euro-deterrent.” Cameron (2025) frames this as a crisis of credibility, while Breitenbauch (2024) shows how European actors may contribute to deterrence through cooperation with the United States and existing NATO operational practices. Related debates on NATO nuclear politics and European strategic autonomy similarly stress the need to align deterrence commitments with allied political consensus highlighting the possibilities and limitations of sustaining a European security framework (Chevreuil, 2025; Fayet et al., 2024; Freedman, 2025). In the Nordic context, Haugevik and Sending (2020) caution that distinct foreign-policy repertoires limit prospects for a common Nordic order, while Braut-Hegghammer and Hagstrom (2026) show how a Nordic deterrence cluster may help overcome certain constraints on bilateral allied postures. These debates do not necessarily converge on a single solution; they reflect, rather, a broader search for ways to reinforce deterrence through incremental, coordinated, and politically feasible measures – often within, rather than outside, the NATO structures. These discussions reinforce the article’s argument: deterrence cooperation is likely to advance through differentiated, reciprocal, politically feasible, and practice-based forms rather than through uniform models of integration.

In alliance theoretical terms, the typology demonstrates how a patron can navigate the abandonment–entrapment dilemma through differentiated integration (see Snyder, 1984). The Nordic experience shows that credibility of commitment, reassurance of allies, and deterrence of the adversary can be sustained, even enhanced, through adaptive software integration, without necessarily relying on more visible, nuclear hardware-based measures that could potentially escalate tension. By adjusting the depth and form of integration to accommodate allied reservations, Washington and the two Nordic states mitigated entrapment risks while preserving strategic alignment and managing burden-sharing within political and strategic limits. In the third nuclear age, such approaches enable small, allied states to contribute with increasingly independent and supplementary roles within extended deterrence arrangements (Braut-Hegghammer & Bowers, 2026; Narang & Vaddi, 2025).

Future research can apply the conceptual framework drawn here to other similar bilateral engagements and compare it to more contrasting cases where allies seek deeper nuclear integration or greater institutional maneuver – such as Poland, the Baltic states, or South Korea. Further investigations can also unpack the micro-level debates that shape the negotiation of these forms of cooperation, focusing on intra-alliance variation across U.S. governmental, military, diplomatic, intelligence, and political circles, capturing any nuances.

As strategic rivalry intensifies and the boundary between conventional and nuclear deterrence blurs, smaller allies will increasingly face the challenge of calibrating participation: preserving autonomy and domestic legitimacy while maintaining access, influence, and reassurance. In an increasingly uncertain alliance order, what becomes more consequential for protégés is the boundary between the negotiables and non-negotiables.

Additional Files

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