Charles Kupchan, a professor of international affairs at Georgetown University, describes Denmark’s decision as part of a broader “re-nationalization of political life that is sweeping Europe.” It’s driven, he says, by continent-wide concerns about immigration, the debt crisis, and a lack of leadership from traditional EU powerhouses, particularly Germany. “The borders of EU member states are effectively coming back to life,” he says. “The developments of the last three to five years raise very troubling questions about the project of European integration. For the first time, it is reasonable to question whether Europe has reached its high-water mark and will either go no further, or will slide in reverse.”

The first signs of trouble for European integration didn’t start with the economic crisis. Kupchan points to failed referendums in France and the Netherlands in 2005, in which voters overwhelmingly rejected the European constitution. Yet the debt crisis has exposed the limits of European togetherness and put member nations on a collision course in ways not seen in decades.

In Germany, resentment is growing at the prospect of more bailouts for spendthrift Mediterranean Europe. Earlier this year, the German newspaper Bild published a photo of a Greek banner that labelled German Chancellor Angela Merkel and French President Nicolas Sarkozy “Nazis,” complete with the yellow stars of the EU flag rearranged into a swastika. The headline blared: “We pay—still we are abused!” Meanwhile, a new survey in the Netherlands found the majority of Dutch (54 per cent) want Greece ejected from the EU rather than continue the bailouts. Fully 60 per cent of respondents said the Netherlands “should stop lending money to other eurozone countries now.”