It is time to face facts: markets are not just betting against the euro but testing the European project itself. Tuesday’s Franco-German summit showed that the more leaders repeat outdated nostrums – such as the impossibility of eurobonds – the less they are believed. The Merkel-Sarkozy proposals were an attempt to paper over differences (with Germanic prudence on eurobonds and debt ceilings balancing Gallic pressure for economic governance) and buy time, but the past few months have shown that this piecemeal approach will simply increase the cost of a long-term solution. To save itself, the European Union must stop seeking loopholes and attacking symptoms, and instead grapple seriously with its fundamental design faults.

Since the French and Dutch “no” votes in 2005, pro-Europeans have acted like the mythical boy with his finger in the dyke; unwilling to give ground for fear of a eurosceptic flood. As a result they have defended the unsatisfactory and unsustainable status quo: a currency not backed by a treasury; joint borders without a common migration policy; and a technocratic foreign policy divorced from national sources of power.

The only way to stop a tide of disintegration spreading beyond the euro to the EU itself is to tackle these problems head on. Doing so, however, means first giving up the dream of a one-speed Europe. EU nations have long travelled at different speeds, but now they need an institutional framework for a multi-speed future.