TUNIS, Tunisia—Marching down a boulevard ringed in razor wire, and in view of armored vehicles mounted with water canons, tens of thousands from across the world called for new measures of liberty and dignity as they descended Tuesday afternoon on Tunis to open the weeklong World Social Forum.

Organizers estimated some 50,000 people took part in the Forum’s opening march, which set off around 4pm under glaring sunshine and blustery winds from Avenue Habib Bourguiba—the site where weeks of demonstrations forced Tunisian dictator Zine El Abidine Ben Ali from power on January 14, 2011, and kicked off the Arab Spring.

The decision to hold this year’s Forum in Tunisia, where the two-year-old popular revolution is now facing mounting threats of a Salafist religious takeover, suggests the importance the country plays as a model for successful democratic transitions.

“If the Tunisian experience leads to a kind of democracy that brings a different conception to countries in Africa and the Middle East, it will give people hope to think that democracy is possible,” said Ahmed Ben Messaoud, an audiologist and supporter of the opposition Patriotic Democratic Unified Party, whose leader, Chokri Belaid, was assassinated in February.

The killing of Chokri—a revered figure who had begun, in under half a year, to mount a serious challenge to Tunisia’s new establishment through the skilled organizing of opposition groups into a coalition known as the Popular Front—unleashed outrage and street demonstrations that led to the resignation of the country’s president.

Meanwhile, Tunisia’s public is quickly losing faith in a government it elected on a temporary basis last October to write and approve the country’s new Constitution—but which, so far, has failed to set new election dates, provide jobs or carry through on other key promises, leading to fears of a longer-term power grab.

“The country is in a big dilemma: Islamists want a totalitarian government, and civil society wants a more open, more secular government,” said Messaoud, speaking at an outdoor café in downtown Tunis several hours before the World Social Forum march began. In contrast to Egypt, where President Mohammed Morsi and his Muslim Brotherhood rammed through a Constitution widely unfavored by a population that saw it as religious overreach, in Tunisia “they’re taking longer—and paying for it with instability.”

“It’s not going to be an easy task to write this Constitution and to lead the country from dictatorship to democracy,” he added. “We’re not just making a Constitution ‘to go’—one that gives the chance of another dictatorship in the future to take over. We want a Constitution for the next generation.”

The global next generation will be on full display here throughout the week as activists and civic organizations engage in hundreds upon hundreds of workshops, panels and strategic discussions to redress universal challenges to human freedom and dignity.

On Tuesday’s march to inaugurate the 2013 World Social Forum—an event which began in 2001 in Porto Alegre, Brazil, and was held there again last year—people chanted and sang and danced as the mile-long tide of bodies swept across Tunis, a sea of flags and banners flowing from the historic boulevard of the Revolution on to Avenue Mohamed V.

From anti-capitalists to Catholics, from white-robed groups representing Western Saharans’ right of independence, to Tunisian parents demanding justice for the government killings of their children in 2011, the marchers continued for five kilometers, weaving in and out of sunshine as they passed under palm trees and finally, in the evening, reached the Menzah Sport City arena for speeches and a rally.

One man who attended, Diego de la Mora, works on budget transparency for the Mexican organization Fundar. He will lead several workshops at the Forum helping civic groups learn how to better hold their governments accountable with budgetary planning. In that sense, he said, the Forum is important as “a means of uniting people with technical expertise.”

“It’s very important for people to know how to fight for their rights,” said de la Mora, “and that means learning to talk in government language.”

Another man, a Tunisian named Gharasch, had a long silver beard and wore a heavy black coat and tinted sunglasses as he walked with the surging crowd. He said he and his wife “came to encourage the revolution. The Forum is for all the youth to help us build democracy.”

This week, we’ll be seeing how some of that building takes place.