The Treaty on Measures for the Further Reduction and Limitation of Strategic Offensive Arms (New START) officially expired in February 2026; the absence of a replacement agreement has undermined the last pillar of nuclear arms control between the United States and Russia. In its official statement, the UN Secretary-General (2026) emphasised that the expiry of New START without follow-up constitutes a serious threat to the global disarmament architecture that has been built up over decades. This situation is not merely a global diplomatic crisis for the European Union. For with the expiry of New START, the era of security enjoyed passively under Washington’s protection has also come to an end.
The argument put forward here is that Europe no longer has the luxury of being hesitant in the face of this vacuum in international law. Europe must utilise France’s military strength to immediately build its own nuclear sovereignty, supported by collective funding. There are three main points of argument to be examined in this paper: first, an analysis of the ‘deterrence gap’ that has emerged following the New START; second, the urgency of responding to the increasingly aggressive global modernisation of nuclear weapons; and third, the effectiveness of France’s strategic decision in March 2026 to extend the scope of its nuclear deterrence eastwards as a response to the uncertainty surrounding the United States’ commitments.
These deeply concerning legal and military realities underpin the urgency of achieving nuclear self-reliance. According to the International Campaign to Abolish Nuclear Weapons (ICAN), the expiry of New START automatically increases the risk of a new arms race on the global stage, as the inspection mechanisms and data transparency that have hitherto limited the number of missing strategic nuclear warheads are no longer in place. The Munich Security Conference (MSC) (2026) refers to this void as a “deterrence gap” in Europe. The US nuclear deterrent, which has long served as the umbrella underpinning Europe’s security posture, is now deemed inadequate, particularly as that sovereignty is contingent upon decision-making processes in Washington that are increasingly bureaucratic and tied to unpredictable domestic political dynamics. A nation’s national interests will always take precedence over alliance commitments within this anarchic international system. This continent is, in fact, staking its very survival on the consistency of external parties without any deterrent instruments directly controlled by European strategic authorities, whilst its strategic focus is beginning to shift permanently away from the Atlantic.
As noted by the Stockholm International Peace Research Institute (SIPRI) (2025), the trend of massive global arms build-up is further exacerbating this situation. According to the summary of the SIPRI Yearbook, as international geopolitical relations deteriorate, nuclear-armed states will continue to expand the operational capacity of their warheads. The U.S. Department of State’s report (2025) to Congress further aligns with this reality. The report indicates that even before the New START treaty officially expired, Russia had already demonstrated a pattern of non-compliance with its obligations regarding long-range inspections. Europe, too, is now compelled to possess a credible balancing force to counter this disparity in information and capability. The report by the European Nuclear Strategy Group of the MSC (2026) emphasises the evaluation of Europe’s current nuclear options, focusing on the fundamental principle of defence rather than any ambition to wage aggression. The fundamental principle of defence here is to ensure that, through a deterrent presence under the continent’s own control, no external power dares to initiate a war on European soil.
The increasingly evident shift in France’s nuclear doctrine has provided the impetus for the implementation of this sovereignty. In a strategic analysis published by the International Institute for Strategic Studies (IISS) (2026), it is noted that France’s decision in March 2026 to extend its nuclear umbrella to Eastern Europe constituted a revolutionary step in the history of European Union defence integration. This move demonstrates that the political foundation has shifted into tangible, measurable action to protect Europe’s collective interests, rather than remaining mere diplomatic rhetoric. A stronger strategic ambiguity has emerged through this collaborative model, wherein an aggressor now faces not only a single decision-making centre in the United States, but must also contend with a decision-making centre in France situated right at the heart of the continent. France is effectively filling the void left by transatlantic uncertainty by expanding the scope of its deterrence. Furthermore, this simultaneously provides new legitimacy for the aspiration of European strategic autonomy, which has often remained mere rhetoric without adequate military instruments.
The main argument underpinning all of the above dynamics is that collective nuclear sovereignty is an absolute prerequisite for Europe’s political existence in the 21st century, and is no longer merely an optional choice. Failure to respond to Russia’s nuclear expansion, as experienced by the European Union, coupled with uncertainty regarding transatlantic security commitments and the ability to act independently, would place the continent in a dangerously vulnerable position. Therefore, France’s decision in March 2026 must be viewed as the last strategic opportunity for EU member states to break free from their chronic dependence on third-party protection. Europe’s position in the global security order will be reduced to that of a mere object of other major powers’ policies if there is a lack of political courage to fund and coordinate this joint nuclear deterrent. Furthermore, Europe will lose its diplomatic clout and leave the security of its citizens dependent on the outcome of elections outside its own continent.
Although the cost of maintaining the collective nuclear deterrent with France is considerable from both an economic and political perspective, when compared with the risk of total economic collapse resulting from a failure of deterrence, this sum is in fact a more efficient investment. Diplomacy without military strength is like music without instruments, as Frederick the Great’s classic dictum goes. To ensure its diplomatic voice retains its weight on an increasingly fragmented global stage, the European Union must equip itself with autonomous defence instruments under France’s nuclear umbrella. As a turning point in the history of European sovereignty, this choice must be fully consolidated by 2026. European leaders must be prepared to see the Blue Continent lose control over the future and security of its own citizens forever if they fail to capitalise on the momentum of the expansion of French deterrence. Europe’s future must be forged by Europeans themselves and must no longer be determined by the outcome of elections in other countries or the collapse of international agreements beyond their control. Europe must attain genuine, credible and fully sovereign military autonomy.
