Everything Changes but Nothing Changes: Can France Overcome its Own Nuclear Doctrine?

In a recent interview broadcast live on French television, President Emmanuel Macron declared:

Ever since there has been a nuclear doctrine since Charles de Gaulle, there has been a European dimension of [France’s] vital interests. I have remained ambiguous on what those vital interests are, just like all my predecessors. Yet, in today’s context, I wish to engage with all partners that are interested, and see if we can go further. Though under some conditions, France will not pay for others’ security, it will not subtract from any security meant for France, and only the French President would decide of its use.

But when asked whether he would be willing to accept the additional risk of defending allies, the president deflected on the strategic environment and denied that those were questions seriously being considered, keeping with the tradition of strategic ambiguity. “Would France trade Paris for Helsinki?” is a recurring question lately. Unlike the United Kingdom, whose nuclear capability already contributes to NATO’s overall capabilities for deterrence and defense, France’s arsenal plays a separate role in the eyes of both NATO and potential adversaries.

Whether its nuclear umbrella also covers Europe has been a debate in France for decades. It began in a period dubbed “the Great Debates,”  which anchored many of the principles in French strategic culture.

Yet, a paradox exists. Currently, French nuclear doctrine doesn’t align with another ambition: European strategic autonomy. If the engagement with European allies must “go further,” France’s doctrine should change as well. The debate today is not only about whether France is capable enough or coming up with a “Euro-bomb” — but also whether its doctrine is still fit for purpose.

The Great Debates: A Political, Not a Strategic Debate

The 1972 White Paper on Defence, meant to lay the foundations of French nuclear doctrine, only made its deterrence posture on Europe unclear. While it asserts that the doctrine is strictly national, it also acknowledges that vital national interests may extend beyond France’s borders. The paper even compares this security guarantee to that of the United States, suggesting that the French approach is more credible to European allies and adversaries alike thanks to ambiguity, since France did not have to reassure its direct neighbors. The strategic ambiguity that was established under General de Gaulle was thus born anew and became stated policy.

Yet this foundation reflected a political more than a strategic mentality: France announced contributing to NATO’s nuclear deterrence with the Ottawa declaration of 1974 while, at home, policymakers and nuclear scholars were increasingly chastised for their pro-European views. In 1976, Guy Méry, the chief of staff to President Valéry Giscard d’Estaing, introduced the concept of “extended sanctuarization.” The concept explicitly moved beyond Gaullist ambiguity of vital interests by affirming France’s nuclear participation in European security, suggesting more clearly that France’s nuclear role could stretch beyond its own territory. Gaullists pounced, branding this a betrayal of de Gaulle’s legacy and painting the president’s camp as anti-Gaullist. For them, any notion of sharing France’s nuclear shield was anathema. “Vital interests” were the French president’s alone to define, leaving no room for European input or joint control. President François Mitterrand (1981–95) fundamentally never resolved the issue by simply letting it fade away. Despite being a staunch Europeanist, he clung to Gaullist ambiguity and national control in nuclear policy, and neither fully embraced the European role nor categorically rejected it — which ensured that he would avoid trial for any anti-Gaullist crime.

As the Cold War waned, France’s nuclear stance began to soften. By 1992, Mitterrand mused about a “European nuclear doctrine.” For France this was more than talk: Paris and London quietly explored ways to align their nuclear policies while French strategists, historians, and politicians began imagining a new European role for France’s force de frappe.

After the 1994 White Paper on Defence and the 1995 election, President Jacques Chirac harnessed this strategic momentum and proposed a “concerted deterrence” for Europe by linking France’s nuclear arsenal to its European allies and partners. But while France did indeed end its Hades program before consulting with Germany, the notion of “strict sufficiency”— limiting the arsenal to the smallest possible deterrent needed to inflict unacceptable damage to a potential enemy — in the doctrine gave way to a more restrictive interpretation, with the era of post-Cold War disarmament in full swing. The president still defined French vital interests and the means to protect them, leaving very little room for consultation, and the momentum behind a Europeanized deterrent naturally faded. Some European countries saw little value in “building Europe starting with the roof,” but it was above all Gaullist purists in France who were fiercely opposed to any link between deterrence and alliance. They played a key role in burying a Franco-German agreement, as part of this concerted approach, during heated parliamentary debates.

Despite periodic bursts of ambition, Europe’s place in France’s nuclear strategy remains largely symbolic and undefined, still hemmed in by Gaullist traditions. This position was made unmistakably clear in President Emmanuel Macron’s official address on March 5, 2025, where he unequivocally reaffirmed that France’s nuclear deterrent is fully sovereign and national. His declaration followed an impassioned political debate, during which numerous parties firmly opposed any move toward a European dimension of deterrence. The Europeanization of French nuclear deterrence thus remains largely rhetorical, as hollow today as it was nearly 60 years ago. As the French saying goes, the more it changes, the more it’s the same thing.

A Doctrine That Goes Further

The perceived stability of French nuclear doctrine among French policymakers and commentators alike has led many to describe it as “chemically pure.” Certain aspects of the doctrine, such as strategic ambiguity, whose meaning has shifted since the Cold War, are now seen as part of a “Gaullist inspiration” that ensures continuity over time. Yet the doctrine’s core concepts are limiting the effectiveness in advancing France’s role in European deterrence, especially if Paris wants to reassure allies considering nuclear proliferation.

Strategic ambiguity allows more room for deterrence according to its supporters, because it prevents an adversary from making risky moves. Conveniently, ambiguity also sidesteps answering tough questions about France’s European commitments. France’s commitments in defending, say, Poland, becomes a question purposefully left unanswered. But while this might work in deterring adversaries, reassuring an ally is completely different. Reassurance requires clear commitments to allies to prevent a feeling of abandonment, and, potentially, proliferation. For instance, the biggest reason why U.S. extended nuclear deterrence is being questioned by some European allies is because Washington’s long term commitments have appeared uncertain. Doing the same thing and expecting a different result — especially given the anticipated presidential 2027 elections — is foolish. If France wants to change its deterrence posture to better reassure its neighbors, and deter not one but several peer competitors, ambiguity is no longer fit for purpose in a multipolar strategic context.

Another concept limiting the possibility of a more Europeanized approach to French nuclear deterrence is the ultime avertissement (final warning). This concept emerged in 1981 in remarks by Prime Minister Pierre Mauroy, who rejected the idea that France’s tactical nuclear capabilities could serve any purpose other than a strategic one. The aim at the time was to shape a doctrine aligned with Gaullist thinking, to secure its political legitimacy despite having the means for a graduated response by using ground-based nuclear missiles. From President Chirac’s 2006 speech onward, and with a much more limited arsenal, the warning became explicitly nuclear and has remained so ever since. This new stance imposes a clear, strict, and readable threshold for adversaries regarding the crossing of France’s vital interests — while remaining ambiguous about what they are. But this stance also inherently limits the range of possible actions, as it requires being ready to risk everything in any nuclear exchange. Complex questions such as “Is the European Union a vital interest for France?” thus become extraordinarily difficult to address, because they touch on matters of national survival.

Moving beyond the concept of ultime avertissement also means recognizing that strict sufficiency is no longer sufficient to deter. As Former British Minister of Defense Denis Healey said during the Cold War, it “only takes a 5 percent credibility of American retaliation to deter an attack [from the Soviet Union],” while “it takes a 95 percent credibility to reassure the allies.” Thus, if it wants to reassure allies, France would have to rethink appropriate levels of sufficiency to demonstrate resolve and flexibility. Currently, the French arsenal is predominantly a survivable dyad, composed of submarine-launched ballistic missiles and air-launched cruise missiles, suggesting that any Russian targeting would necessarily hold at risk French cities. With its deliberate limit of 300 warheads, strict sufficiency also renders possible counter-force strikes limited, similar to the UK’s Moscow Criterion. Having a range of options for nuclear escalation — notably the ability to strike multiple times against adversary forces without immediately triggering full-scale nuclear war — could enhance the credibility of France’s response. By having a more tailored deterrence, it could help to reassure European allies concerned with the risk of uncontrolled escalation, and acknowledging their perspectives could help strengthen European unity. Ultimately, this would require modifying both the quantitative and qualitative composition of France’s arsenal — a shift that could open the door to deeper engagement with partners open to new capabilities.

Thinking of a new French doctrine through the lens of U.S. extended nuclear deterrence is also the wrong approach. Thanks to its membership in the European Union — and even the geographic reality of being a European country — the definition of its vital interests are naturally European. France now has a common currency, borders, institutions, and even a vast amount of diaspora within interconnected European countries. Unlike when “concerted deterrence” was proposed in 1995, France now has the Euro, the European constitution, and rejoined NATO’s integrated multinational military command.

Who to defend is also an open question, but interested European allies like Poland could come directly to France. For instance, Poland could support French strategic exercises to develop interoperability beyond its NATO commitments and participate in France’s long proposed strategic dialogues. This includes supporting the French Poker exercises with air and tanker support, demonstrating both how their strategic interests overlap and how it can extend the reach of French strategic capabilities.

Nevertheless, rather than having allies come to France, the opposite could happen. For example, it could join NATO’s Nuclear Planning Group. This move would clearly demonstrate France’s goodwill towards its allies and significantly enhance cooperation in nuclear matters. But it would also face extraordinary public pushback.

No European Autonomy Without Nuclear Autonomy

Ultimately, the French president remains the only decision maker on French deterrence and can choose whether to follow past doctrine or chart a new course. Nonetheless, doctrine represents an important framework: Time and time again, the collective imaginary of what constitutes French deterrence has often clashed with France’s own ambition to establish European strategic autonomy. The preferred course of action for leadership, then, has been following a consensus instead of challenging the fundamentals. President Macron deserves recognition for his persistence despite the blowback at home.

Yet France’s Gaullist nuclear doctrine is not without merit. It has helped to eliminate the fear of a total defeat like that of 1940 and has firmly established a mindset of national self-reliance. However, the doctrine now conflicts with one of France’s key strategic objectives: autonomous European defense.

Today, openly acknowledging the need for sovereignty is essential to arriving at a new doctrine that is strategically sound. On one hand, public support in France is crucial to strengthen the European credibility of its nuclear deterrence, as opposed to the specter of possible populist victory. On the other hand, a reform of such magnitude directly involves Europeans too. By engaging openly and democratically in discussions about the means and objectives of nuclear strategy, France and Europe would effectively reconnect with General de Gaulle’s true ambitions: securing both French interests and European security ensured by Europeans themselves. As another saying goes, everything must change so it can stay the same.

Paul Cormarie is a policy analyst at the non-profit, non-partisan RAND Corporation. He is a non-resident fellow at West Point’s Modern War Institute and a former Center for Strategic and International Studies Nuclear Scholar.

Florian Galleri is an incoming Stanton post-doctoral Fellow at the Massachusetts Institute of Technology and holds a Ph.D. in French Modern History from Nantes University (France). He regularly writes for Le Rubicon.

Image: Number 10 via Wikimedia Commons

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