A view of a round table session Friday at the G8 summit in L’Aquila, Italy.

L’Aquila, Italy ? For all the smiles and upbeat talk, the just-ended Group of Eight summit showed how unwieldy the forum has become, run by Cold War-vintage powers while relegating the world’s fastest growing economies — China, India and Brazil — to observers.

It also showed just how sharp the divisions are between old-world and new-world viewpoints.

The meeting fell short of expectations on many counts, from climate control to trade. The global economic crisis weighed heavily on everyone and complicated efforts to find consensus, resulting in avoiding or putting off some major decisions. Members appeared divided on how soon to roll back stimulus packages, although they agreed now was not the time to start.

G-8 leaders themselves are quick to point out the shortcomings of a three-decade-old exclusive club in dealing with 21st century problems.

Excluding emerging world powers is “wrongheaded,” U.S. President Barack Obama said Friday in a wrap-up news conference. He also said the creaky system of international institutions, including the United Nations, needs to be overhauled to reflect geopolitical changes.

French President Nicolas Sarkozy called G-8 expansion all but a done deal. Italian leader Silvio Berlusconi, this year’s host, said limiting the club to rich, industrialized nations is “no longer adequate.”

But finding the right formula for an overhaul will prove tricky.

“Everybody wants the smallest possible group … that includes them,” Obama said. Nations not included “think it’s highly unfair if they’ve been cut out.”

Sarkozy said he expected the G-8 to expand to 14 nations — adding Brazil, China, India, Mexico, South Africa and an Arab country — when France holds the rotating presidency in 2011.

But no clear path was laid this week as existing members clung to their elite status.

“They will not give up their power,” said Milena Elsinger of the DGAP foreign policy think tank in Berlin. “They will still meet and they will still pretend to be the leaders of the world.”

The Group of Eight grew out of a democracy-promoting economic forum in France in 1975 of the then-six wealthiest industrial nations, all in the Northern Hemisphere: France, West Germany, Italy, Japan Britain and the United States. The membership was expanded to seven the following year with the addition of Canada, and to the present eight in 1997 when Russia joined. The group meets annually, rotating among the eight countries.

However, in recent years there has been a dramatic expansion and dispersion of global economic power outside the G-8, a trend accelerated by a recession that has hit the U.S. and Europe particularly hard while allowing some developing economies to keep growing.

China is now the third-largest economy in the world after the U.S. and closing in fast on No. 2 Japan. Nonmembers Brazil and Spain both have stronger economies than Canada, which ranked only No. 11 on the 2008 list of world economies by the International Monetary Fund.

“The days in which a handful of European and Atlantic countries could dictate to the rest of the world are passing,” said William Galston, a scholar at the Washington-based Brookings Institution and a former Clinton administration official.

“The G-8 is still useful for discussing items of common interest among the European and North American democracies, but for many purposes it ought to be expanded,” Galston said.

Still, some of the fast-growing new economic powerhouses do not to want to be full members of the club “because they have to accept all the responsibility … they are not ready,” said John Kirton of the G-8 Research Group at the University of Toronto. He said this includes decisions by G-8 members to commit resources and, if necessary, troops to hot spots like Afghanistan.

To many, the so-called Group of 20 — formed last year to combat the spreading global recession — seems more relevant. It includes G-8 countries along with China, India, Brazil and many other fast-growing economies.