What if the government of one Member State deliberately sets out to block or sabotage the Union? Some observers might argue that Europe is already edging toward such a reality. But the more unsettling possibility is that matters could deteriorate further.

A single national veto can be deployed across all areas where EU decisions require unanimity in the Council. This includes foreign and security policy, EU finances—from budgetary resources to the multiannual financial framework and borrowing instruments—as well as key aspects of justice and police cooperation, including operational collaboration. It extends to decisions on enlargement and even to the suspension of a Member State that descends into dictatorship or violates the Union’s foundational principles.

The current geopolitical moment has made this structural weakness impossible to ignore. If the EU hopes to maintain credibility on the world stage, it cannot function under conditions where even issuing a joint statement, let alone approving aid to Ukraine, can be blocked by a single government.

Up to now, four main avenues have been explored to circumvent unanimity—what might be called the Union’s procedural escape hatches: passerelle clauses, enhanced cooperation, Permanent Structured Cooperation (PESCO), and a separate treaty among willing states. Each offers a partial workaround. None offers a definitive solution.

The passerelle clauses—both the general provision and the six policy-specific variants—allow the European Council, or in certain cases the Council of Ministers, to replace unanimity with qualified majority voting (QMV) on particular issues. Yet even here, the irony is stark: the very decision to activate such clauses can itself be vetoed by a single national government.

The mechanism of enhanced cooperation permits a subset of Member States to deepen integration within the EU framework. The treaties require that such cooperation align with Union objectives and remain open to all Member States at any time. It is conceived as a last resort, triggered only when the Council determines that collective action at the level of all Member States cannot be achieved within a reasonable timeframe, and provided that at least nine countries participate.

In these arrangements, all Council members may join deliberations, but only those representing participating states can vote. In the European Parliament, however, all Members retain voting rights. Measures adopted under enhanced cooperation bind only those states that take part.

Though used sparingly, enhanced cooperation has occasionally expanded after its initial launch, with additional Member States joining later. Still, its limitations are significant. Authorization requires a qualified majority in the Council and the consent of the European Parliament—except in foreign and security policy, where unanimity remains mandatory. In that domain, a single government retains the power to block the entire initiative.

Even within enhanced cooperation, participating states could theoretically agree to shift certain decisions from unanimity to QMV among themselves, though this has never occurred in practice. Moreover, such flexibility does not extend to matters involving military or defense implications.

Enhanced cooperation can mitigate deadlock. It introduces a subtle pressure mechanism: the prospect of exclusion may encourage reluctant states to compromise. Yet its reach is limited. In foreign policy, it still depends on unanimity. And it offers no remedy for dealing with a Member State that systematically undermines the rule of law, nor for addressing issues like the EU budget or enlargement.

A more specialized instrument, Permanent Structured Cooperation (PESCO), operates in the defense sphere. It allows Member States with higher military capabilities and deeper commitments to establish structured cooperation through QMV. However, once established, decisions within PESCO require unanimity among participating states.

This creates an inherent tension. While QMV can be used to launch cooperation, the requirement of unanimity thereafter risks reintroducing paralysis. Indeed, reluctant states might join precisely to retain the ability to block decisions from within. In theory, such states could be suspended by QMV if they fail to meet commitments. In practice, this threshold is difficult to enforce.

PESCO thus offers a limited, if somewhat convoluted, pathway around vetoes in defense policy—but only within narrow bounds.

Beyond the formal structures of EU law lies the option of a separate treaty among willing states. Member States may conclude agreements outside the EU framework, provided these do not conflict with existing treaties. Such arrangements can even assign roles to EU institutions.

This approach was famously used in 2012 with the Treaty on Stability, Coordination and Governance—the so-called Fiscal Compact—designed to bypass a British veto. It deepened integration in an area already under EU competence.

Could a similar approach work in foreign and security policy? Only partially. It could facilitate coordination on strictly CFSP matters, including common positions and defense cooperation. But it cannot extend to areas governed by EU law, such as trade sanctions or financial assistance from the EU budget. Nor can it address core institutional challenges like vetoes over the multiannual financial framework, enlargement, or the disciplining of a rogue Member State.

Taken together, these mechanisms offer flexibility at the margins. But they do not resolve the central dilemma. If a Member State were to act in sustained bad faith—blocking decisions, resisting reform, and undermining democratic norms—the Union could find itself effectively paralyzed.

In such a scenario, the EU would face not just a procedural crisis, but an existential one.

What, then, could be done? One radical, yet legally conceivable, solution would be the creation of a Treaty for a New Union. This treaty would replicate the current framework almost entirely, but replace unanimity with QMV—or perhaps a strengthened version of QMV that prevents a small minority from blocking decisions.

It would incorporate the entire acquis communautaire, ensuring continuity of law, commitments, and institutional structures. Member States choosing to join would simultaneously invoke Article 50 to exit the existing Union, effectively transferring their membership to the new framework.

At present, this scenario may seem remote. But it is not without precedent. The mere act of preparing such a treaty could exert pressure on dissenting states to compromise. And if they refuse, a smaller group might proceed regardless, leaving the door open for others to join later.

European integration has advanced in precisely this way before. In 1950, early efforts within the Council of Europe stalled under opposition from Britain and Nordic countries. The breakthrough came when six states forged ahead with the European Coal and Steel Community, embodying Paul-Henri Spaak’s principle of faire l’Europe avec ceux qui veulent faire l’Europe. Others followed in time.

A similar dynamic emerged in the 1980s. Amid the stagnation of “Eurosclerosis,” the European Parliament advanced the Spinelli draft treaty, proposing deeper integration even without universal participation. Though initially divisive, the initiative catalyzed momentum. The 1985 European Council in Milan, through an unprecedented majority vote, launched treaty reform despite resistance from several states. Those same states ultimately joined the process rather than risk exclusion, culminating in the Single European Act.

The lesson is clear. The credible threat of moving forward without unanimity has, at key moments, been the engine of European progress.

Today, the EU may again face such a moment. To place the option of a new treaty on the table is not to abandon unity, but to preserve it. Without such leverage, the Union risks accepting paralysis—unable to act decisively, unable to defend its values, and vulnerable to those who would exploit its institutional constraints.