By STEVEN ERLANGER and STEPHEN CASTLE


PARIS - With uncertain leadership and few powerful collective institutions, the European Union is struggling with the strains the world economic crisis has inevitably produced among 27 countries with uneven levels of development.

The traditional concept of“solidarity”is being undermined by protectionist pressures in some member countries and the rigors of maintaining a common currency, the euro, for a region that has diverse economic needs. Particularly acute economic problems in some newer members that once were part of the Soviet bloc have only made matters worse.

Europe’s difficulties are in sharp contrast to the American response. President Obama has just announced a budget that will send the United States more deeply into debt but that also makes an effort to redistribute income and overhaul health care, improve education and combat environmental problems.

Whether Europe can reach across constituencies to create consensus, however, has been an open, and suddenly pressing, question.

“The European Union will now have to prove whether it is just a fair-weather union or has a real joint political destiny,”said Stefan Kornelius, the foreign editor of the German newspaper Suddeutsche Zeitung.“We always said you can’t really have a currency union without a political union, and we don’t have one. There is no joint fiscal policy, no joint tax policy, no joint policy on which industries to subsidize or not. And none of the leaders is strong enough to pull the others out of the mud.”

Thomas Klau, Paris director of the European Council on Foreign Relations, an independent research and advocacy group, said,“This crisis affects the political union that backs the euro and of course the E.U. as a whole, and solidarity is at the heart of the debate.”

The crisis also has implications for Washington, which wants a European Union that can promote common interests in places like Afghanistan and the Middle East with financial and military help.

“All of that is in doubt if the cornerstone of the E.U. - its internal market, economic union and solidarity - is in question,”said Ronald D.Asmus, who runs the Brussels office of the German Marshall Fund.

The problems are basically twofold: within the inner core of nations that use the euro as their common currency, and within the larger European Union.

The 16 nations that use the euro - introduced in 1999, and one of the proudest European accomplishments - must submit to the monetary leadership of the European Central Bank. That keeps some members hardest hit by the economic downturn, like Ireland, Spain, Italy and Greece, from unilaterally taking radical steps to stimulate their economies.

Within the larger European Union, fissures are growing between older members and newer ones, especially those that lived under Soviet socialism. Some countries of Central Europe, like the Czech Republic and Poland, are doing relatively well. Others, including Hungary, Romania and the Baltic states, are in a state of near-meltdown.

But only two newer members - tiny Slovenia and Slovakia - are protected by being among the countries that use the euro, and there was little support at the emergency summit meeting in Brussels on March 1 for changing the rules to allow more to join quickly.

Many new members have seen their currencies plummet against the euro. That has made their debt repayments to European banks, their primary lenders, a much greater burden. Some countries are asking for aid, both from their European partners and from the International Monetary Fund, to prop up their currencies and the banks.

Having watched the Soviet Union collapse, the countries of Central and Eastern Europe embraced the liberal, capitalist model as the price of integration with Europe. That model is now badly tarnished, and the newer members feel adrift.

Mr.Klau sees a worrying loss of faith in a certain brand of capitalism.“It’s politically dangerous there since they’ve just emerged from an ultraregulated and stifling system, were confronted with shock therapy that created great hardship, and are just beginning to recover and stabilize,”he said.“Now they’re thrown back into an economic and political cauldron.”

The new members are finding that their European partners are putting their own national interests ahead of“collective and necessary solidarity,”Mr.Klau said.

Charles Grant, director of the Center for European Reform, a research group in London, is more sanguine, however.“My expectation is that the euro zone countries, out of pure self-interest, will bail each other out,”he said.“For Central and Eastern Europe it is too early to say there won’t be solidarity. But non- E.U. countries in the east - particularly Ukraine - seem to be the No.1 worry.”

The leaders of European Union countries who gathered March 1 in Brussels included, from left, Sergei Stanishev of Bulgaria, Nicolas Sarkozy of France, Andrus Ansip of Estonia, Demetris Chistofias of Cyprus, Mirek Topolanek of the Czech Republic and Lawrence Gonzi of Malta.