"Most of the euro zone periphery is out of recession by now," said Holger Schmieding, chief economist at Berenberg Bank in London, which has calculated that even Greece is growing again. "That is absolutely good news. The rebound in the economy is ultimately the solution to almost everything."
In Frankfurt on Wednesday, the European Central Bank outlined plans to search for and expose all the bad loans and damaged investments lurking in euro zone banks. That effort would be the first step in forcing banks to fix their problems so they can start lending again. Without lending to businesses and home buyers, there can be no sustained economic growth.
Maybe more important, the review of large banks was a sign that euro zone leaders, who sometimes appear out of touch, had made concrete progress on policy. Their decision last week to designate the European Central Bank as top banking cop is intended to de-Balkanize the euro zone banking system. A single currency, they argue, should have a single banking system.
Shares of European banks fell after the central bank disclosed details of the planned bank assessment, but in a strange way that may have been a good sign. It meant investors expected the central bank to be tough and thorough, culling the sick banks and freeing the healthy ones from the stigma attached to euro zone lenders. Earlier efforts by a patchwork of national regulators to conduct supposed "stress tests" on Europe's banks proved woefully inadequate.
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There have been other hopeful omens lately, like an increase in European car sales in September from 20-year lows. Ireland, once one of Europe's most troubled countries, said recently that it expected to emerge from its bailout program by the end of the year.
On Wednesday, a closely watched survey showed that French businesspeople were becoming slightly more optimistic because of an uptick in exports. In Germany, the euro zone's first among equals, the Christian Democrats led by Chancellor Angela Merkel are edging toward an accord with the Social Democrats to form a government. That would end a de facto freeze on euro zone policy making while Ms. Merkel was preoccupied with domestic politics.
Few economists are ready to pop open the Prosecco just yet — not after a crisis that has lasted five years, and with unemployment in the euro zone still at 12 percent. Youth unemployment in several countries is three or four times that. But Nicolas Véron, a senior fellow at Bruegel, a research organization in Brussels, said that the bank cleanup, as it unfolds during the coming year, could help inspire a broader return of confidence.
"There is a sort of happy scenario where this becomes a game-changer and creates a chain of positive consequences that really boost European growth," Mr. Véron said.
(Read more: Is the euro the next currency battleground?)
He said that he still had doubts things would turn out that well.
In fact, it is impossible to talk about Europe without mentioning everything that could still go wrong. Nowhere is growth particularly strong. Mujtaba Rahman, director for Europe at Eurasia Group, a political consulting firm, said that political leaders had still failed to give the central bank the tools it needs to do the job. There still is not an adequate source of money to recapitalize sick banks, nor is there a mechanism to gently wind down those that cannot be saved.