In that sense, the protest movements in democracies are not altogether unlike those that have rocked authoritarian governments this year, toppling longtime leaders in Tunisia, Egypt and Libya. Protesters have created their own political space online that is chilly, sometimes openly hostile, toward traditional institutions of the elite.

The critical mass of wiki and mapping tools, video and social networking sites, the communal news wire of Twitter and the ease of donations afforded by sites like PayPal makes coalitions of like-minded individuals instantly viable.

“You’re looking at a generation of 20- and 30-year-olds who are used to self-organizing,” said Yochai Benkler, a director of the Berkman Center for Internet and Society at Harvard University. “They believe life can be more participatory, more decentralized, less dependent on the traditional models of organization, either in the state or the big company. Those were the dominant ways of doing things in the industrial economy, and they aren’t anymore.”

Yonatan Levi, 26, called the tent cities that sprang up in Israel “a beautiful anarchy.” There were leaderless discussion circles like Internet chat rooms, governed, he said, by “emoticon” hand gestures like crossed forearms to signal disagreement with the latest speaker, hands held up and wiggling in the air for agreement — the same hand signs used in public assemblies in Spain. There were free lessons and food, based on the Internet conviction that everything should be available without charge.

Someone had to step in, Mr. Levi said, because “the political system has abandoned its citizens.”

The rising disillusionment comes 20 years after what was celebrated as democratic capitalism’s final victory over communism and dictatorship.

In the wake of the Soviet Union’s collapse in 1991, a consensus emerged that liberal economics combined with democratic institutions represented the only path forward. That consensus, championed by scholars like Francis Fukuyama in his book “The End of History and the Last Man,” has been shaken if not broken by a seemingly endless succession of crises — the Asian financial collapse of 1997, the Internet bubble that burst in 2000, the subprime crisis of 2007-8 and the continuing European and American debt crisis — and the seeming inability of policy makers to deal with them or cushion their people from the shocks.