Diplomats and politicians have voiced rising concern over Germany’s direction in recent years, whether in striking a contentious gas-pipeline deal with Russia or blocking NATO membership for Georgia and Ukraine.

The leading philosopher Jürgen Habermas warned recently that Germany had become a “self-absorbed colossus.” The financier George Soros said this summer in a speech in Berlin that the government was “endangering the European Union” with its economic policies.

Germans, most of whose salaries and standard of living have not improved as the economy has strengthened, are more disenchanted than ever with the financial demands of the European Union. Questions about Germany’s commitment to the bloc found renewed urgency during the Greek debt crisis, which had threatened the stability of the euro, but signs had emerged well before that.

In the rush to pass the Lisbon Treaty, an accord intended to increase the European Union’s political and foreign policy powers, Germany’s Federal Constitutional Court in Karlsruhe declared in June 2009 that the country’s constitutional identity “is not open to integration” and that the public perception of politics remained connected “to patterns of identification related to the nation-state, language, history and culture.”

While the court approved the treaty with several conditions, the strident tone of the decision was cause for alarm among supporters in Berlin and Brussels of a more unified Europe. A confidential analysis prepared for the president of the European Parliament said that the decision meant “this far and no further” for European integration.

The resistance to new demands partly reflects the transformation Germany has undergone in recent years. The country fused a dynamic economy in the West with a bankrupt one in the East. Germans were forced to realize that foreign guest workers were never going home  one-fifth of its residents are now immigrants or of immigrant background. The return of the capital to Berlin and the construction of a national Holocaust memorial stirred the nation’s darkest memories.

“It’s not like the 1930s, where the jackboots are going to be stomping into other countries,” said William M. Drozdiak, the president of the American Council on Germany. “But having moved the capital from Bonn back to Berlin, there has been a profound psychological change, shifting the center of gravity to the east, with Germany thinking more like a Central European power.”