How does France’s nuclear deterrent contribute to the defense of Europe?

France’s nuclear deterrent, serving first and foremost to defend France’s vital interests, also contributes to the defense of Europe. This contribution has been recognized within the North Atlantic Alliance since 1974, but remains little known. In a speech closely followed by France’s European partners and its adversaries alike, President Emmanuel Macron announced a new concept for French nuclear deterrence: “forward deterrence” (dissuasion avancée). This article aims to explain the origins of this concept, outline its main pillars, and describe the partnerships that are sought. It then discusses the relationship with the U.S. doctrine of “extended deterrence”, and finally offers some ethical considerations.

A historical overview of the French nuclear deterrent

France’s first efforts to develop a nuclear weapon date back to the mid-1950s. Based on scientific research that had begun even before World War II under the leadership of Frédéric Joliot-Curie, France’s goal at the time was to acquire the industrial capability, particularly for the production of fissile material, to build its first weapon in the early 1960s. The main strategic rationale was that in order to survive in the post-World War II world, it was essential to possess nuclear weapons. This reasoning was fueled largely by Soviet nuclear blackmail and a lack of American backing to resist it, during the Franco-British operation in Suez in 1956.

Upon his return to power in 1958, General de Gaulle found a well-advanced nuclear program in place, enabling the first French nuclear test on February 13, 1960. He deliberately steered the program toward the creation of a fully sovereign and independent nuclear strike force, convinced that in this domain, decisions cannot be shared – especially with a more powerful ally that does not necessarily have the same interests. American hostility toward this policy of nuclear independence, coupled with NATO’s adoption of the “flexible response” doctrine – widely perceived in Paris as an elastic doctrine allowing the U.S. to avoid nuclear involvement in the defense of Europe – led to France’s withdrawal from NATO’s integrated military command in 1967. The reflections on nuclear doctrine conducted under the aegis of General Lucien Poirier, as set out in the 1972 White Paper on Defense, clearly stated that a country’s vital interests could be defined only by “reference solely to that country itself”.^[1] The perception that the French nuclear deterrent protected France – and France alone – thus became firmly established both in France and among its European allies. Nevertheless, the same 1972 White Paper emphasized that the limits of these vital interests must necessarily remain vague and that the logic of deterrence relies on a degree of uncertainty. Noting that France was not isolated and existed within a web of intertwined interests with its European neighbors, it thus pointed out that France’s nuclear deterrence strategy was a determining factor in European security. General de Gaulle had, in fact, clearly stated back in 1963^[2] that nuclear weapons could, if necessary, play a part in protecting France’s allies. The contribution of France’s nuclear deterrent to the defense of Europe was recognized by its allies at the 1974 NATO summit in Ottawa. The final communiqué acknowledged that the two European states possessing nuclear forces were capable of playing a distinct deterrent role that contributed to the overall strengthening of Europe’s deterrent. It was primarily the role of London and Paris as a second decision-making center – complicating the adversary’s calculations – that this acknowledgement highlighted.

Nevertheless, the notion that the French deterrent served exclusively to defend France persisted throughout the Cold War, as evidenced by a famous exchange that took place in June 1987 during a meeting of G7 heads of state and government in Venice.^[3] Asked by Margaret Thatcher about the use of French nuclear weapons were Bonn to be invaded by the Soviets, François Mitterrand replied that such a scenario would mean that the deterrent had failed. This was a situation that must not be allowed to occur. And, moreover, the mission of protecting the Federal Republic of Germany and Western Europe was the responsibility of the North Atlantic Alliance, not that of France.

However, the post-Cold War era and the construction of a political Europe in the 1990s led French statesmen to attempt to integrate this European dimension into their national deterrent more effectively. It had certainly been present since the beginning but had never been properly developed. In 1995, French Prime Minister Alain Juppé proposed to Germany the concept of “concerted deterrence” between the two countries. This proposal did not meet with a favorable response at the time. The lack of interest in the French deterrent among European countries, starting with Germany, during a period of happy globalization and the United States’ continued commitment to NATO, would thus persist for some thirty years. The only country with which France made progress in this area during that period was the United Kingdom.

The Franco-British nuclear axis

Political talks between the two European nuclear powers led to the creation of a Joint Nuclear Commission in 1992. The initial discussions within this framework focused on comparing the two deterrents in terms of concepts and doctrines, missile defense, and nonproliferation. These discussions revealed that the two countries’ nuclear doctrines were closely aligned. In late October 1995, British Prime Minister John Major and French President Jacques Chirac issued a statement (the so-called Chequers Declaration) in which they affirmed that they could not identify any situation in which the vital interests of one of the two powers might be threatened without those of the other power also being threatened. This declaration was systematically reiterated in the following years by the leaders of both nations, including after Brexit, until it was reinforced by the Northwood Declaration in 2025. This bilateral agreement clearly signaled a strong strategic alignment regarding the vital interests of both nations. Studies on the adoption of a joint air-launched nuclear missile, the ASLP^[4] were conducted, but without success. The British ultimately rejected this option, given the risks it could pose to their nuclear relations with their American ally.

Reciprocal port calls by nuclear-powered ballistic missile submarines (SSBNs)^[5] also took place, with some British SSBNs calling at Île Longue in Brittany, the base for French SSBNs, while some of the latter were seen calling at Faslane in Scotland. The significance of these reciprocal port calls was essentially symbolic, however, and in no way reflected cooperation in the operational sphere, particularly regarding SSBN patrols.

The Anglo-French axis was further strengthened in 2010. As part of a broader treaty on defense and security cooperation (Lancaster House Treaties), French President Nicolas Sarkozy and Prime Minister David Cameron signed an agreement on joint radiographic and hydrodynamic facilities necessary for their simulation program. The main facility covered by this treaty, known as EPURE, is located at the headquarters of the French Alternative Energies and Atomic Energy Commission (CEA) in Valduc, France. Although the facility is shared, hydrodynamic testing is conducted independently.

The France-UK partnership gained significant momentum in July 2025, during a meeting at Northwood between British Prime Minister Keith Starmer and French President Emmanuel Macron. Against a backdrop of announcements regarding U.S. disengagement from European defense, the two leaders reaffirmed the close relationship between their countries in the area of nuclear deterrence. In particular, they reinforced the 1995 declaration, stating that “France and the United Kingdom agree that there is no extreme threat to Europe that would not prompt a response by our two nations.”^[6] The joint declaration also announced deepened cooperation and coordination across nuclear policy, capabilities and operations.

The Franco-British partnership in the nuclear sphere, which is continuing to grow stronger, stands as firm evidence of the European dimension of the French deterrent. It is also, so far, the only such evidence, pending the developments announced by President Macron on March 2, 2026. This partnership, uniting the continent’s only two nuclear powers, is fundamental to the future of European defense. In the coming months and years, it will be interesting to see what tangible progress will be announced in the area of operational cooperation. The main factor that could limit the development of this cooperation, however, remains the very strong, existential link between British and American deterrence, particularly in terms of manufacturing and technology.

Forward nuclear deterrence

French nuclear doctrine is typically articulated in France through speeches delivered by the head of state. Generally, there is one such speech per term of office. It provides an opportunity for Presidents of the Republic to reaffirm the fundamentals of French doctrine, to affirm their personal commitment, and to provide the necessary political credibility to the national deterrent. Or, where appropriate, announce changes. In 2001, for example, President Jacques Chirac stated that France’s deterrent contributed to Europe’s security and that its primary role – since its beginnings in the 1960s – was to ensure that France’s survival would never be threatened by a military power with hostile intentions. He additionally said that it must also enable France to confront threats to its vital interests posed by regional powers possessing weapons of mass destruction. In this context, he announced a strategic nuclear weapons plan that would enable France to possess a sufficiently diversified – and therefore flexible – arsenal to ensure the credibility of its deterrent under all circumstances, regardless of the location or nature of the threat.

In February 2020, President Macron delivered this speech for his first term in office. In it, he asserted that France’s vital interests now had a European dimension. He expressed the hope that a strategic dialog would develop between France and willing European partners on the role of the French nuclear deterrent in Europe’s collective security. This was a year in Europe in which illusions about the peace dividends of the post-Cold War era still held. It was marked by the election of President Biden and the warming of transatlantic relations following President Trump’s first term, and above all by the Covid pandemic on which the efforts of all European governments were focused. In such a context, the French proposal received no response.

Six years later, in a completely changed geopolitical context, on March 2, 2026, Emmanuel Macron gave a speech at Île Longue, the base for France’s SSBNs. This speech got a very different reception. Taking note of the increasingly hostile global environment, Russian revisionism – a major risk for Europe and France – the rapid expansion of China’s nuclear arsenal, but also the growth of those of North Korea, Pakistan and India, and the reordering of U.S. strategic priorities, the French president announced a strengthening of France’s deterrent to address this combination of threats. In a bold and assertive tone, he announced an increase in the number of nuclear warheads held by France, rejecting any nuclear arms race but seeking a balanced and coherent level of operational effectiveness for the deterrent in this new global context.

But probably the most important announcement in this speech concerned the concept of “forward nuclear deterrence”. This is the tangible manifestation of the European dimension of the French nuclear deterrent. The fundamentals of the French deterrence doctrine remain the same: strictly defensive in nature, a refusal to engage in nuclear battle, a clear firebreak between conventional and nuclear force; the possibility of resorting to a single, non-repeatable nuclear warning should an adversary misjudge France’s vital interests, and, above all, decision-making that remains the exclusive prerogative of the French authorities. This concept allows for the development of a French deterrence strategy that extends deep into European territory, sending strong signals to both allies and adversaries.

“Forward deterrence” will be implemented gradually, within bilateral frameworks, to respect various political sensitivities among partners choosing to adopt this approach. It may include participation in exercises by French nuclear forces, for example the participation of aircraft in Strategic Air Forces^[7] exercises. It may also take the form of participation in strategic signaling actions, aimed at demonstrating to an adversary the shared resolve of European partners not to yield to any threats. It may involve the ad-hoc deployment of FAS assets, such as Rafale fighters equipped with French missiles, or refueling aircraft, to these partners’ air bases. To be clear, this in no way envisages the permanent deployment of nuclear weapons on partners’ territories, but only on an ad-hoc and temporary basis, for example in the event of an escalation of a crisis.

In early March, when this speech was delivered, eight countries had expressed their interest to France in this “forward deterrence” approach. Alongside the United Kingdom, which is linked to France through the Northwood Declaration, Germany, Poland, the Netherlands, Belgium, Sweden, Greece and Denmark have expressed interest in the “forward deterrence” concept. Bilateral coordination bodies have been established or will be established very soon. On May 27, 2026, Norway also joined this initiative.

Forward nuclear deterrence, U.S. extended deterrence, and circumvention of deterrence

Several questions arise regarding this new concept of forward deterrence, two of which are particularly significant. The first concerns its relationship to U.S. and British extended deterrence within the NATO framework. The second concerns its relevance in the face of hybrid attacks seeking to circumvent deterrence from below, with the potential for the adversary to seek territorial gains and achieve a fait accompli.

The French doctrine of deterrence took shape from the 1960s onward amid a complicated relationship with American deterrence. France’s determination to develop an independent nuclear force stemmed from French doubts about the United States’ willingness to commit to the nuclear defense of Europe in the event of a Soviet attack, given that U.S. territory could then be at the mercy of Soviet intercontinental ballistic missiles (ICBMs).

The U.S. response within NATO, aimed at preventing a recurrence of the French situation and nuclear proliferation by countries asking the same questions as Paris, was the extended deterrence system as we know it today. At the center of this system are the Nuclear Planning Group, of which France is not a member, and the countries possessing dual-capable aircraft (DCA), capable of deploying American B61 bombs using a dual-key system. The associated doctrine is that of nuclear war limited to the European theater. This limitation is made possible by the U.S. non-strategic nuclear arsenal based in Europe or at sea on the one hand, and on the other by the U.S. strategic arsenal and its counterforce strike capability, particularly against enemy command centers and strategic nuclear forces. This doctrine is therefore quite different from the French doctrine which refuses to engage in nuclear battle but carries the risk for the aggressor of a more rapid escalation to extremes in the event of an attack on vital French interests.

This American doctrine has prevailed with most of France’s European partners, which partly explains the lack of response to French proposals put forward in the post-Cold War period (see above). Compared to American military strength – both conventional and nuclear – the French deterrent was clearly not considered credible enough to protect anything other than France itself.

President Trump’s return to power, his softer approach to Russia, and his aggressive stance toward his European allies have clearly changed the perception of some of France’s allies.

In response to criticism that the French cannot match American capabilities, it is worth noting that while the number of nuclear warheads is certainly important – particularly in a counterforce doctrine like the American one – a smaller number of nuclear weapons, such as those in the French arsenal, is capable of inflicting damage from which no country, however vast, can recover. President Macron thus emphasized that the SSBN in front of which he gave his March 2 speech had a firepower equivalent to all of the bombs dropped during World War II.

Moreover, France’s unwillingness to engage in a limited nuclear war stems largely from the fact that such a so-called limitation may make sense for a power located on another continent, but not for a power situated directly within the theater of conflict.

Another frequently heard criticism is that if the French doubted that the Americans would risk New York to protect Paris, why would the French take this risk to protect Tallinn or Warsaw? The answer again lies in the asymmetry of the stakes. French interests are clearly too closely tied to those of their European partners, both within the European Union and within NATO, for an attack threatening the survival of one of them not to be perceived as a vital threat.

All in all, the concept of forward deterrence is quite different from the extended deterrence provided by the United States to its European allies. It is not intended to replace it, but rather to complement it. This was stated very clearly by the French president in his speech.

Another major issue raised in the speech was the challenge of managing conflicts below the nuclear threshold. This issue is, of course, not new to nuclear strategy in general. It had already been the subject of numerous debates in France during the Cold War. But during the post-Cold War period, the French conventional armed forces played a predominantly expeditionary role, unrelated to the deterrence strategy in Europe. As a result, reflection in this area had diminished. Recent conflicts in the Ukraine and Middle East have highlighted the threat of drone or ballistic missile strikes, including those targeting a nuclear-armed state. Faced with this type of threat, the French president clearly emphasized the need for France and its European allies to acquire early warning and extended air defense capabilities to counter such threats. He also advocated the acquisition of conventional deep-strike capabilities to provide options for managing escalation. These three areas, in which France expects clear support from its allies – particularly through the various initiatives already launched^[8] – provide conventional support to the nuclear deterrent.

Although not mentioned in the president’s speech, it is necessary finally to note the threats from cyberspace and information warfare, which can also undermine nuclear deterrence. Coordination among Europeans in these areas can and must be improved.

Ethical considerations

It is always difficult for the author of these lines – a former commander of a SSBN and head of the nuclear forces division of the French Joint Defense Staff – not to talk about ethics when writing an article on nuclear deterrence, particularly in a journal called Ethics and Armed Forces. There is a paradox in being prepared to use nuclear weapons, with their catastrophic consequences, to prevent France and its allies from being attacked and having their vital interests harmed. This raises moral questions. Of course, anyone involved in the development and operationalization of nuclear deterrence in whatever capacity – political, military, scientific or industrial – has to deal with the dilemmas posed by nuclear weapons. But in the democracies in which we are fortunate to live, these questions also arise for the citizens of countries that deploy deterrent forces, as well as for the citizens of countries which benefit from those deterrent forces. The aim here is not to list all the dilemmas or to theorize about whether nuclear deterrence meets the criteria of a just war,^[9] but rather simply to summarize the question as the author of this article sees it today: “If it is morally desirable to pursue nuclear disarmament, can we do so under the current circumstances of a world of autocratic predators who disregard international law?” The answer regarding France’s maintenance of a credible deterrent seems obvious; but this can only be done under the conditions, which France respects, of a strictly defensive doctrine. The use of nuclear weapons as a means of coercion – as Russia is doing in its war of aggression against Ukraine, for example – must be rejected.

President Macron also addressed this ethical dimension on March 2. He stated that beyond the consolidation of France’s nuclear deterrent and its embedding in Europe through the concept of “forward deterrence”, France remains committed to the long-term goal of a world without nuclear weapons. Acknowledging the end of a significant portion of the European security architecture that was built during the Cold War and its aftermath by the two nuclear superpowers, but without the Europeans, he called for the eventual reconstruction of a new security framework between the Europeans and the Russians, prioritizing European security interests above all else. The strategic considerations developed within the framework of forward deterrence will help to better organize European convergence in this area. This is also one of the key challenges of this new concept.

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The current strategic context is characterized by predatory policies in Europe and beyond, alongside a North Atlantic Alliance weakened by a U.S. administration moving away from the shared values on which the Alliance was founded in 1949. This clearly calls for a European response. This response begins with the political cohesion of European states, who must not forget that, whatever their individual political differences, today’s Europe was built on the ruins of Nazi and Communist totalitarianism. It certainly requires an increase in each European country’s financial commitment to defense. But it also requires a clearer definition of how the British and French deterrents should contribute to European security. The concept of “forward deterrence” proposed by President Macron addresses this need for France by sending strong signals about the European dimension of France’s vital interests. While it does not provide nuclear security guarantees, its objective is to ensure that no enemy determined to threaten the survival of a European ally would believe that France would fail to respond – including in the nuclear domain. Furthermore, it is accompanied by a call for a European security architecture in which Europe is a key player in determining its own security tools. Bilateral talks between France and its partners who support this approach will therefore be crucial for the defense and security of Europe as a whole.