Twelve months ago, Europe's leaders celebrated the EU's "big bang" expansion from 15 to 25 states. Today, they are staring into a black hole, as the French referendum threatens to rip apart their grand plans overnight.
"I am not sure there will be a big candle," said one EU diplomat, referring to the May 1 anniversary of entry into the bloc of 10 countries -- including eight ex-communist states from central Europe -- which marked the continent's historic reunification half a century after it was ripped apart by war.
The EU newcomers -- Cyprus, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia and Slovenia -- of course have much to celebrate after joining the rich club they had worked towards for so long.
But even those wanting to fete the first birthday of the enlarged bloc admit that it is clouded by the looming May 29 French referendum on the EU's new constitutional treaty.
The repercussions of a French "non"
The constitution, signed among much fanfare in Rome last October after some four years of wrangling, is designed to prevent decision-making gridlock in the expanded Union. To come into force, it must be ratified by all 25 EU states. Diplomats have long conceded that it could be rejected in a small number of countries, but have suggested ways of getting round the problem could in most cases be found.
But a "non" in France, a founding member of the European project in 1957 and long a driving force of the EU along with Germany, is another matter entirely.
"There is a strong chance that France will vote "no", which would probably kill off the treaty for good," said Daniel Keohane of the Center for European Reform.
Apathy and skepticism
The current threat of a French 'no,' while unexpected, did not come completely out of the blue. Anyone watching closely over the last 12 months would have seen the warning signs.
The fireworks which erupted across Europe last May 1 fizzled out barely a month later, when European Parliament elections confirmed two trends which have long threatened the EU: euro-apathy and euro skepticism.
Then came the fiasco surrounding the nomination of a new EU commission, centered on the unedifying spectacle of EU leaders horse-trading to avoid an openly anti-gay commissioner, Rocco Buttiglione (photo), being put in charge of civil rights across Europe.
But undoubtedly more controversial was the EU's decision in December to give Turkey a green light to start talks on joining the bloc.
The prospect of the vast Muslim majority country one day becoming the EU's biggest state only fuelled anti-EU feeling among those concerned that the EU was going too far beyond its original aim.
Indeed, French President Jacques Chirac was so worried that anti-Turkish feeling could color his planned EU constitution referendum, that he insisted on delaying a start date for Ankara's EU entry talks until October.
The Bolkenstein directive
But then, just as the EU's plans seemed to be on the rails, French anti-EU campaigners succeeded in drawing public attention to a hitherto little-noticed draft EU law, for some arcane issue of services sector deregulation.
The so-called Bolkestein directive has become the focus for broader concerns, notably France's diminishing influence in the EU, which many French fear is veering too far towards an Anglo-Saxon free market model.
No more Europe?
Whatever the reasons for a "no" vote, most people agree that a French rejection of the constitution would lead at the very least to a period of inertia, and at the worst to a gradual break-up of the entire project.
"There will be no more Europe," said former EU Commission chief Romano Prodi recently. "We will go through a great period of crisis. The problem will not only be a catastrophe for France, but the fall of Europe."