Nearly every nation in South America has been jolted by large protests or violent clashes in recent weeks, a continental surge of antigovernment anger unlike anything in years.
On the streets of Venezuela, opponents of the left-wing government are squaring off against riot police nearly every day. In Paraguay, angry crowds sacked and firebombed the country’s parliament building after lawmakers tried to alter presidential term limits. Powerful unions in Argentina crippled the country’s transportation networks this month with a general strike.
Whether leftist or right-wing, the governments of Brazil, Colombia, Chile,Ecuador and even tiny French Guiana are all facing major demonstrations, abysmal approval ratings or both.
The political dynamics vary across the continent, but analysts see common threads. The global commodity boom that ushered millions of South Americans into the middle class has burned out, crimping government finances. And a more politically engaged and plugged-in citizenry has lost patience with rank corruption and the feints of authoritarian leaders who chip away at democratic checks on their power.
In several countries, populist leaders who cast themselves as national saviors and demonized their opponents have turned electoral contests into supercharged life-or-death showdowns, making democratic transitions and ideological compromise all the more difficult. 
“South America is part of a global pattern, marked by a search for fresh and effective political leadership in agitated and often polarized societies,” said Michael Shifter, president of the Inter-American Dialogue, a Washington think tank, noting significant protests recently in South Africa, Russia, South Korea and the United States.
That South America is more unstable than it has been in many years shouldn’t come as a surprise either, Shifter said, given the level of economic malaise across the continent. “The region has a strong tradition of protest that tends to come in waves — and is particularly pronounced when long-standing deficiencies are revealed,” he said.
Those shortcomings were a lot easier to gloss over when global prices for oil, iron ore and the region’s other export commodities were high, leaving treasuries flush. Spending the money freely was a surefire way for populist leaders to stay in power.
Led by Venezuela’s Hugo Chávez, a generation of charismatic left-wing leaders dominated elections through the first decade of the millennium, including Brazil’s Luiz Inácio “Lula” da Silva, Ecuador’s Rafael Correa and the Argentine power couple of Nestor Kirchner and his wife, Cristina Fernández de Kirchner, who succeeded him. 
With big personalities and an appeal to nationalism, they won support by conspicuously rejecting “neoliberal” policy nostrums such as reducing the size of government and privatizing state-owned industries. Those leaders also tapped into frustration with state institutions seen as too servile to the wealthy, but in many instances old elites were replaced by new ones with close ties to the government, creating fresh resentment.
Even the most successful populists have also run into problems at times of leadership change, despite electoral wins that kept their parties in power. Venezuelan President Nicolás Maduro has struggled badly in the shadow of Chávez. Lenín Moreno, who narrowly won Ecuador’s presidential election this month, ran on a campaign of continuing Correa’s leftist policies. But Luis Verdesoto, a political analyst in Quito, said Moreno will take office as a weakened figure lacking a strong coalition.
“Populist leaders have always struggled to transfer votes,” Verdesoto said..
Ecuador’s opposition continues to reject its loss and protest in the streets. Election authorities have agreed to a partial recount. International observers declared the vote fair, but the standoff has left the country split.
Venezuela remains the region’s most explosive crisis. The latest protests erupted after its supreme court — packed with judges loyal to Maduro — tried to strip the country’s opposition-controlled legislature of its authority last month.
At least five people have been killed since then in the country’s most sustained antigovernment protests in three years. Maduro’s opponents are demanding new elections, a release of political prisoners and respect for democratic norms.
“The narrative [of populist leaders] was that the rich had always controlled institutions and the law for their own benefit, and the proposal was: Now we will take over the institutions and use them for the common good,” said Gabriela Calderon, a Latin America analyst at the Cato Institute in Washington. 
“But the reality turned out to be more of the same, only with different faces at the helm,” Calderon said. “Institutions and laws are still being used to project rather than to limit power, and to protect the powerful from those who would challenge them.”
When lawmakers in Paraguay last month passed a constitutional amendment allowing the country’s conservative president, Horacio Cartes, to run for a second term, antigovernment crowds stormed the parliament building and set it ablaze. They saw the move as a power grab in a country where democracy returned in 1993 after four decades of military rule. 
In Argentina, center-right businessman Mauricio Macri won Argentina’s presidency in late 2015 running largely as an anti-populist. But the country remains polarized, and Macri has faced crippling strikes led by activists and unions loyal to Fernández de Kirchner.
Even nations like Chile and Colombia that don’t fit the populist trend have seen large street protests this month against incumbents weakened by low approval ratings and anemic growth.
The corruption scandals nagging at nearly every government in South America have also brought people into the streets. The true legacy of several of the region’s big-spending leaders is just beginning to come to light, but the governments of Lula, Chávez and others are accused of deepening the corruption they claimed to be cleaning up.
The giant Brazilian construction firm Odebrecht won billions of dollars worth of contracts across Latin America to build bridges, ports and other public works projects, but is now at the center of Brazil’s sprawling Car Wash investigation, the biggest bribery scandal in the country’s history. 
Odebrecht paid nearly $800 million in bribes, according to prosecutors in Brazil, the United States and Switzerland. Dozens of its former executives have provided plea-bargain testimony alleging illegal payouts to politicians, including top members of President Michel Temer’s cabinet. Temer’s approval rating hovers around 10 percent, and the latest in a series of major anti-corruption protests occurred in late March.
“Anger over corruption is really the one thing that unites Latin Americans right now,” said Brian Winter, editor of the Americas Quarterly journal. It’s partly a reaction to the economic downturn, he said, “but it’s also the product of a middle class that has grown by 50 million people over the last decade.” 
Those families “are paying taxes now and they care about good governance,” added Winter, “and they are smart enough to know that’s impossible unless the old way of doing politics in Latin America changes.”