SÃO PAULO, Brazil -- Just a few weeks ago, Mayara Vivian felt pretty good when a few hundred people showed up to a protest she helped organize to deride the government over a proposed bus fare increase. She had been trying to prod Brazilians into the streets since 2005, when she was only 15, and by now she thought she knew what to expect.
But when tens of thousands of protesters thronged the streets this week, rattling cities across the country in a reckoning this nation had not experienced in decades, she was at once thrilled and dumbfounded, at a loss to explain how this could have happened.
"One hundred thousand people -- we never would have thought it," said Ms. Vivian, one of the founders of the Free Fare Movement, which helped start the demonstrations engulfing the nation. "It's like the taking of the Bastille."
The impassioned mass protests thundering across Brazil have swept up an array of grievances -- from costly stadiums and corrupt politicians to high taxes and shoddy schools -- and spread to more than 100 cities Thursday night, the most yet.
All of a sudden, a country that was once viewed as a stellar example of a rising, democratic power finds itself upended by an amorphous, leaderless popular uprising with one unifying theme: an angry rejection of politics as usual.
Much like the Occupy movement in the United States, the anti-corruption protests that shook India in recent years, the demonstrations over living standards in Israel or the fury in European nations such as Greece, Brazil's demonstrators are fed up with traditional political structures, challenging the governing party and the opposition alike. And their demands are so diffuse that they have left Brazil's leaders confounded as to how to satisfy them.
"The intensity on the streets is much larger than we imagined," said University of São Paulo philosophy student Marcelo Hotimsky, another Free Fare Movement organizer. "It's not something we control, or something we even want to control."
Even after politicians in São Paulo, Rio de Janeiro and other parts of Brazil ceded to protesters' initial demands by rolling back bus fare increases this week, the demonstrations continued to spread Thursday night, and President Dilma Rousseff delayed a trip to Japan amid the crisis.
In Brasília, the capital, police used pepper spray to prevent protesters from reaching Congress, but some changed course and marched on other modernist landmarks in the city, smashing windows at the Foreign Ministry and scaling the Meteor, an iconic marble sculpture in the reflecting pool at the ministry's entrance.
"I saw the youth taking to the streets, and I wanted to support them," said Raimundo Machado, 50, a public servant in Brasília, who is worried about Brazil's beleaguered public health system.
"I pay for a health plan, but I can pay. What about those who can't?" he added.world