Although the European Union's 27 member states are formally equal, the reality is that there are huge differences between them. The two largest and most economically important, Germany and France, are also two of the EU's founding members. Their disproportionate political influence within the bloc cannot be denied.

Before the two came together in the 1950s, as part of the European Coal and Steel Community, their longstanding enmity had torn Europe apart through countless wars. With Germany's total defeat and partition in 1945, West Germany - under US protection - and France had a chance to reconcile and lay the foundation for a lasting peace.

The 1957 Treaty of Rome not only helped to accelerate the reconstruction of war-torn Western Europe; it also established a new (Western) European political order. By permanently integrating West Germany and France, it finally eliminated the traditional source of major European wars. It is no exaggeration to say that the reconciliation of these two traditional enemies after World War II is the reason why the EU exists today.

But it wasn't always smooth sailing. In 1954, an early attempt to establish a European Defense Community was derailed when the French National Assembly rejected the idea. Similarly, in 2005, the French (along with the Dutch) shot down an effort to create a Constitution for Europe.

Now, the French far right, after finishing first in this year's European Parliament election, led French President Emmanuel Macron to dissolve parliament and call a snap election. Once again, the future of the EU hinges on the question: What do the French want?

This question has returned at an especially inauspicious moment: Russian President Vladimir Putin's invasion of Ukraine has brought war back to Europe, and former US President Donald Trump currently looks well positioned to return to the White House next January. If Marine Le Pen's National Rally wins the French election, and Trump wins in November, what will become of Europe? Would the European project be able to survive such a confluence of forces?

France, after all, is indispensable to that project. If either it or Germany ever broke away from it, the show would be over. To be sure, the EU has 25 other member states, and all of them are important - some more so, and some less. But Europe can live with an Italian government led by a party with neo-fascist roots. If the French far right secures a majority in this summer's election, and Le Pen goes on to win the presidential election in 2027, that would be a totally different matter.

The rise of a neo-nationalist government and chief executive in France would threaten the very fabric of the Union. Europe's other internal enemies, such as Hungarian Prime Minister Viktor Orbán, would feel even more emboldened to stand in the way of EU policymaking. Worse, this would be happening just when the EU needs to strengthen itself in the face of a broader geopolitical and technological realignment.

While France has always been susceptible to nationalist narratives, Germany - owing to its history - has long been immunized against such illusions. But a victory for the National Rally would force Germans to confront a policy question that we thought had been put behind us: Do we belong to the West, or are we really part of the East, after all?

Pro-Russian populist parties such as Alternative für Deutschland and the Bündnis Sahra Wagenknecht are openly pressing this question. Sadly, they have been gaining ground, at least in eastern Germany.

An alliance between Trump and Le Pen, with Putin looming in the background, would add dramatically to the chaos that already lies in store for Europe. The big winners would be Putin and his geopolitical patron, Chinese President Xi Jinping. Putin would make a decisive step toward achieving his strategic objective: To restore Russia's status as a global power, and then wield it hegemonically over Europe.

For Europe, this would be a collapse into parochialism - an act of pure self-destruction. Given the fraught global political environment, Macron has placed an especially risky bet by calling a snap election. It is a gamble that could well decide Europe's future. If it fails, that could mean "Rien ne va plus!" (no further bets) for Europe.

From Project Syndicate