As Europe faces an increasingly complex security environment, questions around the continent’s future defence posture have taken on renewed urgency. The spectre of Russian aggression, underscored by the ongoing war in Ukraine, as well as the imminent return of Donald Trump to the White House, will force European leaders to re-examine longstanding assumptions about collective defence, nuclear deterrence, and the changing character of conflict. Central to these discussions are the roles of the United Kingdom and France as Europe’s primary nuclear powers and the growing importance of the cyber and space domains as crucial battlegrounds of the 21st century and beyond.
Nuclear Deterrence in a Multipolar World
Since the end of the Cold War, the strategic calculus surrounding European nuclear weapons has been fundamentally redrawn. No longer is the continent caught between the bipolar standoff of the United States and the Soviet Union. Instead, Europe must now navigate a multipolar nuclear landscape characterised by the rise of additional nuclear-armed states like China, India, Pakistan and North Korea.
In this context, the independent nuclear arsenals of the UK and France take on heightened significance. With around 225 and 290 atomic warheads, respectively, Britain and France possess the third and fourth-largest stockpiles in the world.[1] These capabilities provide a critical backstop to NATO’s overall deterrence posture and lend credibility to Article V of the North Atlantic Treaty, which states that an attack on any one ally shall be considered an attack on all.
Yet, as NATO faces internal strains, exemplified by tense relations between the US and key European allies during the previous Trump administration, questions have emerged about the long-term reliability of the American nuclear umbrella. In 2019, French President Emmanuel Macron controversially described NATO as “brain dead,” warning that Europe could no longer take US support for granted.[2] Concerns have also been raised about the alliance’s nuclear sharing arrangements, under which American nuclear weapons are based in Belgium, Germany, Italy, the Netherlands, and Turkey.[3]
Against this backdrop, some strategists have argued that Europe needs a more robust, independent nuclear deterrent centred around the UK and France. Such a “Eurodeterrent” could theoretically operate outside of NATO structures and provide a distinctly European counter to Russian and other nuclear threats. Proponents point to France’s Force de dissuasion, with its mix of air, sea, and land-based delivery systems, as a model to build.[4]
However, the political, financial, and technical barriers to greater Anglo-French nuclear cooperation remain formidable. Both countries have traditionally viewed their nuclear forces as instruments of national sovereignty and are unlikely to place them under any joint command. The immense cost of modernising and expanding nuclear capabilities is another obstacle, mainly as European defence budgets are strained amid the ongoing conflict in Ukraine and commitments to arm and supply those forces. Perhaps most importantly, any move towards an independent Eurodeterrent risks undermining NATO cohesion and provoking a rift with the United States. Therefore, a bilateral agreement between the UK and France is more likely. However, rebuilding and modernising conventional forces is a pressing issue that needs to be resolved sooner.
Cyber and Space: The New Domains of Conflict
Even as Europe grapples with enduring nuclear challenges, the rapid evolution of conflict presents strategists with many new frontiers. Chief among these are the cyber and space domains, where the speed of innovation is outpacing existing doctrines and upending traditional notions of deterrence and warfighting.
In the cyber realm, Europe has emerged as a prime target for state-sponsored hacking, disinformation, and sabotage. Notable incidents like the 2007 attacks on Estonia, the 2017 NotPetya malware campaign, and the SolarWinds breach of 2020, amongst others, have laid bare the scale of the cyber threat from state and non-state actors.[5] In response, the EU and NATO have taken steps to bolster their cybersecurity posture, including creating the European Cybersecurity Competence Centre and the NATO Cyber Operations Centre to provide research, training and support.
Yet much work remains to integrate cyber capabilities into Europe’s broader defence architecture. A key challenge is understanding what constitutes a hostile attack in cyberspace and how the principle of collective defence should apply. Some allies, like the UK, France, and the Netherlands, have been more forward-leaning in attributing cyber attacks to state actors and threatening retaliatory measures.[7] Others, like Germany, have been more cautious, fearing escalation.
The space domain presents a similarly fluid and complex landscape. As outer space becomes increasingly congested, contested, and competitive, Europe’s reliance on space-based assets for everything from navigation to communications to early warning has made it highly vulnerable to disruption. Russia and China’s development of anti-satellite weapons has further heightened these risks, as demonstrated by Russia’s destructive ASAT test in November 2021.[8]
For Europe, enhancing space security will require a multi-pronged approach. This strategy should include increased investment in space situational awareness and resilience, as well as the development of norms and rules of the road for responsible behaviour in space. The EU establishment of the European Union Agency for the Space Programme (EUSPA) and the continued development of its sovereign Galileo and Copernicus systems are positive steps in this regard. However, deeper cooperation between the EU, ESA, and NATO will be essential to ensuring a unified European approach to space.[9]
Strengthening European Strategic Autonomy
Underpinning all of these challenges is the broader question of European strategic autonomy. As the world becomes more multipolar and threats more diffuse, Europe must be able to act decisively and independently to protect its interests and values. However, this pathway requires a comprehensive approach encompassing complex military capabilities and economic, technological, and diplomatic tools.
In the defence realm, initiatives like the European Defence Fund, PESCO, and the European Defence Agency are helping to pool resources and build capacity across the continent.[10] However, more must be done to reduce duplication, enhance interoperability, and streamline procurement processes. European leaders should also consider increasing defence spending towards the NATO benchmark of 2% of GDP and beyond while strategically aligning these investments.
Ultimately, Europe’s future defence will hinge on its nations’ ability to act in unison while leveraging their unique strengths. The UK and France’s nuclear arsenals provide a critical foundation for deterrence but must be integrated into a broader European security architecture. Mastering the cyber and space domains will require a combination of technological prowess, normative leadership, and operational agility. Above all, Europe must cultivate the political will and strategic culture necessary to confidently confront and resolve an uncertain future, with or without the US leading the cause.
[1] Arms Control Association. (2021). Nuclear Weapons: Who Has What at a Glance.
[2] BBC News. (2019). Nato alliance experiencing brain death, says Macron.
[5] CyberPeace Institute. (2021). Playing with Lives: Cyberattacks on Healthcare are Attacks on People.
[6] European Commission. (2021). The European Cybersecurity Competence Centre and Network.
[8] Secure World Foundation. (2022). Global Counterspace Capabilities: An Open Source Assessment.
[9] European Space Policy Institute. (2023). ESPI Yearbook 2023.
[10] European Defence Agency. (2022). Coordinated Annual Review on Defence Report 2022.