Geopolitics and domestic politics are shifting in parallel. A new poll shows that 73 percent of Europeans believe that the continent must ensure its own defense. Distrust of the United States is at a record high. Against this backdrop, one would think we would be witnessing the genesis of a true European defense union, led by France and Germany.
Instead, Franco-German defense cooperation is faltering. Germany is on the verge of abandoning the joint fighter jet project (FCAS) because France’s Dassault Aviation insists, in essence, on developing the key component alone. The common tank program (MGCS) is running roughly a decade behind schedule; this time it is Germany’s Rheinmetall that sees no benefit in cooperating too closely with the French.
Indeed, Germany’s rearmament drive is largely national rather than European. Berlin is pushing a European air-defense shield built around US and Israeli systems, sidelining the Franco-British-Italian alternative. To replace Starlink, Berlin is developing its own satellite communications network rather than pushing for a European one.
Not even US President Donald Trump’s wrecking ball approach to alliances has been enough to overcome the industrial rivalries that continue to obstruct deeper defense integration in Europe. Paris and Berlin seem stuck in old national reflexes despite grandstanding speeches about the Zeitenwende (“historic turn”) or a Europe souveraine (“a sovereign Europe”).
The problem runs deeper than economic nationalism or defense firms dictating policy to governments, though. France and Germany are struggling to cooperate on defense because they lack a shared strategic imperative. Paris promotes Europe-only solutions, while among political and military elites in Berlin the transatlantic reflex continues to kick in—out of habit, and because Germany ultimately still relies on the US nuclear umbrella for its security.
This is why the nuclear question sits at the core of Europe’s defense dilemma. Much else—trust among European capitals, shared strategic and operational concepts to counter Russia—are all tied up with it. If Europe wants a credible and coherent defense posture, this question must be addressed now.
A Wind of Change
President Emmanuel Macron repeatedly offered former Chancellors Angela Merkel and Olaf Scholz a dialogue on nuclear deterrence. Both declined. Their strategy was to strengthen Germany’s conventional forces in the hope that a greater German contribution to NATO would persuade Washington to maintain its nuclear commitment. Berlin was therefore unwilling to contemplate nuclear deterrence without Washington, especially as the issue long remained toxic in German domestic politics.
That calculus is changing. Chancellor Friedrich Merz understands that without addressing the nuclear question, Germany will remain structurally dependent on the US—and therefore vulnerable to both security and economic pressure. Merz has recently confirmed that exploratory nuclear talks are under way with France and the United Kingdom, even if they remain at an early stage.
Public opinion is moving even faster. Our DGAP-Forsa poll from December 2025 shows that 75 percent of Germans support Franco-German talks on nuclear deterrence, up from 54 percent in March of the same year. Notably, even a majority of Green voters—traditionally opposed to nuclear weapons—now favor such discussions.
A similar shift is visible in France. A December 2025 poll found that 64 percent of French voters support sharing nuclear deterrence with Germany, with only 35 percent opposed. The devil is obviously in the details of what “nuclear sharing” would really entail. However, the result is striking given the symbolic status of the force de frappe, launched by former French President Charles de Gaulle in 1960 and long regarded as an untouchable pillar of national sovereignty.
This domestic backing matters. For French nuclear deterrence to be credible in a European role, it must rest on broad political consensus. Berlin will inevitably ask how the far-right Rassemblement National (RN) views the issue, especially as it could win the next French presidential election in 2027. While RN officially opposes sharing the nuclear “button,” younger party figures are increasingly open to European defense thinking. It is notable, too, that RN leader Jordan Bardella has in recent weeks sought to distance himself from Trump, talking up the need for Europe to stand up to US coercion.
What Needs to Be Tackled
President Emmanuel Macron is expected to deliver a long-prepared speech on France’s nuclear doctrine on March 2 at Ile Longue base in Brittany—the base of France’s nuclear submarines. The central issue is likely to be extended deterrence: the role of France’s nuclear forces in protecting other European countries.
For decades, French presidents have spoken of the “European dimension” of French deterrence without ever defining it. Strategic ambiguity has served Paris well. But if France is serious about reassuring Berlin and other capitals—and potentially compensating for a reduced US role—ambiguity will no longer suffice.
At the core lies a fundamental decision for France, Germany, and ideally the United Kingdom: Do they want to build a European system of nuclear protection that is compatible with, or embedded in, NATO? Such a choice would have far-reaching consequences. Three stand out.
First, there are the infrastructure questions. Would France and possibly the UK agree to station nuclear weapons in other EU countries, as the US does within NATO? Would they deploy their own air forces, or allow partner air forces to deliver nuclear weapons in extremis? This may raise questions about European countries’ non-proliferation commitments and may also be seen by Russia as an escalation.
Second, there are questions pertaining to the actual strategic weapons. Extended deterrence would require a significant expansion of French and British arsenals and delivery capabilities. An important question is how exactly this would be financed. Financial reality matters also in securing RN’s support. With persistently high deficits, even a France governed by RN would struggle to reject substantial German financial contributions.
Third, there is the doctrine question. What would a European deterrence doctrine look like? Under what conditions would nuclear force be used? So far, these issues have always been decided by France alone. However, Paris once proposed a “concerted deterrence” to Germany in the late 1990s. But Berlin was unwilling to engage. This however, contributed to France seeking greater nuclear cooperation with the UK, leading to the Lancaster House Treaty of 2010. The treaty established an explicit inclusion of the other country’s security in their respective definitions of their national vital interest in their nuclear doctrines: “We do not see situations arising in which the vital interests of either France or the United Kingdom could be threatened without the vital interest of the other also being threatened,” says the document.
A Structured Dialogue
In his forthcoming speech, Macron should invite key European partners into a structured dialogue on these issues. Crucially, France must avoid presenting a fully-formed unilateral blueprint. Any sustainable arrangement must be co-created with partners, addressing their concerns and giving them genuine ownership. Nothing would be more damaging than a “take it or leave it” proposal from Paris.
This should also not be framed as a purely EU project. Some member states will opt out. A flexible, multi-speed approach—led by France, Germany, and potentially the UK—is both realistic and necessary.
On the German side, the newly created National Security Council could be the ideal forum to respond and manage the subsequent process. It provides the institutional framework to discuss nuclear issues at the highest political level. Bilaterally, the Franco-German Defense and Security Council under the Treaty of Aachen could host a working strand on deterrence.
Trickle Down
With a neo-imperialist Russia on Europe’s eastern border, there is no credible security without nuclear deterrence. Addressing the nuclear question for Europe is thus imperative.
But it could also yield benefits for defense cooperation in the conventional domain.
It would demonstrate that Germany is serious about European strategic autonomy, by helping build a security structure within, or compatible with, NATO that can function without the United States. The signal would be political, psychological, and strategic.
Furthermore, trust forged through nuclear cooperation would spill over into other defense domains. Nuclear coordination demands shared thinking on long-range missiles, air defense, escalation management, and the interaction between nuclear and conventional forces. It would force alignment across the entire strategic spectrum. As Macron said at the Munich Security Conference on February 13, nuclear cooperation is the “cornerstone” for European defense integration, as it forces Europe “to articulate nuclear deterrence in a holistic approach of defense and security. This is a way to create convergence in our strategic approach and culture between Germany and France.”
In short, such alignment may help to ensure that Europe’s defense build-up does not end in a nationally driven—and thus disjointed and expensive—exercise, but becomes a true common project that gives Europeans agency in the world and allows them to defend their interests vis-à-vis Beijing, Moscow, and Washington.
Chancellor Merz and President Macron carry a historic responsibility to move beyond current Franco-German tensions and seize the present window of opportunity—before the French presidential election in 2027 potentially closes it. By tackling the nuclear question now, they can set an anchor for renewed cooperation, revive a Franco-German engine weakened by nearly a decade of stasis, and lay the foundation for a truly independent Europe.
Joseph de Weck is IPQ’s Paris columnist. Elias Ricken is a research assistant at the German Council on Foreign Relations’ (DGAP) Europe center. Jacob Ross is a research fellow at the DGAP’s Europe center, focusing on France and the Franco-German relationship. Shahin Vallée is a senior associate fellow at DGAP’s Europe center.
