“These buffers are extremely important,” Williamson said in a telephone interview. “The market reaction has been exaggerated. I don’t see any major reason to expect a slowdown in growth in the long run.”

That’s small comfort to governments struggling to stay ahead of the rising expectations of disaffected young people, said George Friedman, chief executive officer of policy-risk consultant Stratfor.

“There’s a number of regimes who’ve built their legitimacy on fast growth,” Friedman said in a telephone interview from Austin, Texas, where Stratfor is based. “When they can no longer deliver, they’re setting themselves up for a huge fall.”

Social Media

Reflecting that anxiety, Turkish Prime Minister Recep Tayyip Erdogan blamed social media for fueling protests against his government’s plans to build a shopping mall in an Istanbul park.

“Right now, the same game is being played in Brazil,” Erdogan told supporters in the northern province of Samsun on June 22. “The symbols are the same, the posters are the same. Same Twitter, same Facebook, same international media. They are being controlled by the same center.”

If turmoil does spread around the world, leaders who have held power longer could be voted out of office or see support plunge, Sharma said. These include Vladimir Putin in Russia, Prime Minister Manmohan Singh’s nine-year government in India and the decade-long run for Rousseff’s Workers’ Party in Brazil, he said.

In the wake of Brazil’s protests, approval of Rousseff’s government plunged to 30 percent from 57 percent in June, putting at risk an expected re-election bid next year.

Electorate Wrath

“The same incumbents who benefited from the boom are now facing the wrath of the electorate,” said Sharma, whose 2012 book “Breakout Nations” criticizes the BRICs for not investing wisely during the boom years. “Leaders didn’t fully realize how much was due to global factors and not their governance.”