Toward a More Autonomous European Nuclear Deterrent: Focusing on Fundamental Pillars

European nuclear deterrence has recently resurfaced as a fundamental policy problem in the context of an eroding rules-based international order and weakening arms control treaties. A revisionist, nuclear-capable, and war-prone Russia, as well as a US government that questions the NATO alliance, are only the most recent manifestations of this broader trend. Often, the end design of a new European nuclear deterrent – whether continued dependence on the US, a strengthened British-French nuclear umbrella, an independent European deterrent, or merely a build-up of conventional capabilities – takes center stage in policy debates (e.g., Bunde et al., 2026). The inherent “strategic cacophony,” marked by divergent security interests and threat perceptions (Meijer and Brooks, 2021), will most likely prevent European powers from reaching a swift conclusion on these highly political matters. At the same time, the rapidly evolving security context demands prompt action. In the following, I will argue that focusing on the fundamental pillars of effective deterrence needed in any potential end-state scenario is a more useful approach for European policymakers.

The starting point for any optimal deterrence strategy is that it meets central criteria to guarantee maximum effectiveness. Effective deterrence rests on the adversary’s assumption that a nuclear first strike will, in any plausible scenario, inflict unacceptable damage or immense destruction upon them (Cimbala, 1995). According to deterrence theory, this will render a first strike highly unlikely and help prevent aggression, provided that second-strike consequences can be credibly communicated to the adversary. In this regard, at least two fundamental criteria form the backbone of any effective deterrence strategy: severity and credibility. Severity encompasses threatening an opponent with the prospect that any potential benefits will be outweighed by the costs of a strike, for example through a powerful, extensive, and modern nuclear arsenal. But effective deterrence goes beyond the number and size of nuclear warheads. The adversary must also be made to believe that, in the event of aggression, the opponent is both willing and capable to retaliate.

These main criteria can be further subdivided into more specific conditions that should be fulfilled for effective deterrence. In the following, I will particularly draw attention to one of these, survivability, which is arguably the most crucial for ensuring credible deterrence. Survivability ensures that a nuclear arsenal can withstand a first strike and still be available for retaliation. In other words, it preserves the capability to conduct a retaliatory strike (Sethi, 2023). At the core lies, of course, the survivability of the nuclear arsenal itself, as without any warheads or delivery platforms, no counterattack can be mounted. In this regard, a fully developed, dispersed, and mobile nuclear triad is essential. This triad enables nuclear warheads to be delivered from land, sea, and air via land-based intercontinental ballistic missiles (ICBMs) in hardened silos or mobile launchers, sea-based submarine-launched ballistic missiles (SLBMs) deployed on nuclear-powered submarines, or air-based bombers. Typically, nuclear-powered submarines are considered the most technologically advanced and survivable asset due to the difficulty of tracking them. While survivable nuclear forces are necessary for retaliation, they are not sufficient. A survivable nuclear command, control, communication, and intelligence (C3I) system is also required (Acton, 2025). A survivable C3I system must enable at least three functions. First, it must detect any strike underway. Second, information on strikes must be reported to the responsible authority and enable a decision. Third, orders on whether to retaliate must be transmitted to nuclear forces (Acton, 2025). Ensuring survivable C3I therefore requires the development of complex systems that are resilient, redundant, and secure.

While discussion on an end-state design will unlikely lead to conclusions in the near term due to the prevailing strategic cacophony, taking decisions on certain assets related to the survivability of nuclear forces, as well as C3I systems, will prove considerably easier. This is because some of them have multiple use cases that go beyond a purely nuclear function and are therefore more likely to attract investments from multiple European partners. Furthermore, they are crucial for any effective active missile defense system, which is in the interest of most European countries. This is most obviously the case for systems essential to C3I. For example, early warning systems crucial for detecting ICBMs, SLBMs, or airborne nuclear attacks, or for monitoring potential targets for retaliatory action, can equally be used for detecting conventional precision strikes or serve broader dual-use purposes (Kalyan, 2025).

The current opportunity window for pushing these actions is uniquely favorable and should be used. According to data from a representative Ipsos survey from April 2025, only a very small percentage of citizens oppose a European nuclear deterrent independent of the United States, while broad public support across Europe’s major economies is striking (see Figure 1). With Trump’s intensified challenges to NATO, this support has likely increased. The favorable political headwinds have already pushed European states to intensify nuclear cooperation. While France and the UK have historically collaborated, cooperation with Germany, Poland, the Netherlands, Belgium, Greece, Sweden, and Denmark is something new and already signals an increased embedding of French nuclear capacity within Europe’s broader deterrence architecture (Scazzieri, 2026).

Figure 1: own graph based on data from Tarasco (2025)

Focusing on common investments and progress in the fundamental pillars of effective deterrence is also strategically sound, as these measures are compatible with multiple end-state designs. This means that such decisions do not require first resolving the question of the preferred end-state scenario. Hence, in addition to being politically more feasible, they also allow for a direct strengthening of Europe’s strategic autonomy. For example, space systems are a fundamental pillar in any end-state scenario. They form a key component of communication, early warning, and intelligence systems. Shared investments in enhancing these capabilities at the European level, and reducing strong US dependency, will be beneficial for European countries under all scenarios considered (Süß, 2026). A similar case can be made for the development of active missile defense systems or military communication systems that are cyber-resilient or resilient against electromagnetic shocks, as well as many other assets crucial for credible survivability.

At present, Europe’s survivability posture is characterized less by the absence of core capabilities than by their uneven distribution across national and alliance layers. The submarine-based leg remains the most robust element of the deterrent, anchored in UK and French SSBN forces and complemented by US deployments in the European theatre. Air-based nuclear sharing, supported by ongoing modernization of dual-capable aircraft and forward storage sites, enhances geographic dispersion but does not fundamentally eliminate first-strike vulnerability given the fixed and increasingly transparent nature of base infrastructure (see Figure 2). In parallel, NATO’s NC3 system and national command architectures introduce a degree of redundancy in consultation, communication, and control functions; however, these remain segmented across US, NATO, UK, and French chains of authority without a fully integrated escalation-management structure (Freedman, 2025; Kristensen et al., 2025; Bunde et al., 2026). The most salient deficiencies therefore do not lie in the absence of assets, but in the lack of system-wide integration, persistent reliance on US global early-warning and intelligence, and the incomplete interoperability between parallel command systems, particularly France’s exclusion from NATO’s nuclear planning framework. In Figure 3, the uneven distribution of military satellites among major nuclear powers and European states becomes particularly apparent. Moreover, no European state possesses an early-warning satellite system. Such systems are increasingly state of the art, typically consisting of space-based infrared sensors deployed across multiple orbital layers and supported by ground-based radars (Acton, 2025).

Within this configuration, prioritising investments in dual-use enabling capabilities appears strategically rational precisely because they strengthen survivability across multiple end states. Space-based surveillance, early-warning architectures, and resilient command and communication networks constitute foundational enablers for both nuclear and conventional deterrence, and are therefore more likely to attract sustained multilateral support. Importantly, such investments do not in themselves violate existing arms control treaties, as most agreements regulate deployed warheads, delivery systems, and launch infrastructure rather than C3I architectures or early-warning systems. However, they can still have significant arms control and non-proliferation implications at the level of strategic stability. Improvements in survivability, redundancy, and secure communications – particularly in space-based sensing, hardened networks, and rapid information processing – may be perceived as enhancing first-strike coordination or damage-limitation potential, even if designed solely to ensure assured second-strike retaliation. Mitigating this risk will likely require tailored strategic communication with both allies and potential adversaries to clarify intent and preserve transparency where possible.