Students march during a protest against the government of President Daniel Ortega in Managua, Nicaragua, on Wednesday. (Rodrigo Arangua/AFP/Getty Images)

It’s a protest movement nobody saw coming. For more than a week now, tens of thousands of Nicaraguans have been out on the streets protesting the Sandinista government of President Daniel Ortega. They’ve faced tear gas and bullets that have left more than 30 dead. Yet far from fading, the protests have grown. The citizens have begun tearing down the propaganda billboards and metal trees that Ortega’s government have so carefully erected in the country’s towns over the past 10 years. University students are calling for a new government.

Several protest groups have started talks with the government. Whether that dialogue succeeds or fails, Ortega’s government now looks much less stable than it did just two weeks ago.

Given the intensity of the protests, what triggered them sounds surprisingly small: a modest pension reform that raised taxes between 1 and 4 percentage points and cut benefits by 5 percent.

Needless to say, that’s not the whole story. Ortega has spent more than a decade dismantling Nicaragua’s democracy. His Sandinista Party has stolen elections for the Nicaraguan congress and stacked the judiciary with cronies, and controls nearly every mayoral seat. The president reformed the constitution to grant massive concessions to a Chinese developer for a canal that will never be built plus projects that benefit Ortega’s party, allies and family. He has tried to silence dissent by buying off many of the major media outlets. The Sandinista-controlled courts allowed Ortega to run for a third term in 2016, which he won under blatantly unfair conditions.

So now Nicaraguans are manning the barricades over pension reform? Really?

Maybe it’s not as surprising as it seems. Most of Ortega’s previous abuses were abstract — fiddling with underlying rules of the game, stacking the deck in his favor, stealing from small numbers of citizens who could not effectively oppose him. But pension reform is one of those issues that affect everyone intimately. The elderly who receive only a few hundred dollars per month from the system need that money to eat and buy medicine. All employees and employers contribute to the system.

Pensions everywhere are politically tricky. (It’s no coincidence that experts on Washington often refer to Social Security reform as the “third rail of American politics.”) It’s not that you can’t reform pensions; it’s that you can’t reform them unless you have the people on your side. You need their confidence. They have to believe that the government has their best interests at heart as it ventures to transform something so essential to their lives. In other words, you need legitimacy.

The past few years have taught this lesson again and again. Brazil’s toxically unpopular President Michel Temer, who was never elected but instead succeeded Dilma Rousseff after her controversial impeachment, has found it nearly impossible to reform Brazil’s ruinously expensive pension system. Surprise: His approval rating is stuck in the single digits. By contrast, Argentina’s Mauricio Macri managed to pass limited pension reform in December after his party’s legitimate midterm election victory, and even that victory came with protests and a political cost. Macri succeeded only because he has the legitimacy that Temer doesn’t, and which Ortega has squandered over a decade of authoritarian drift.

To be clear, Ortega’s pension reform wasn’t some wonkish, technocratic proposal. He had to put it forward because the system is teetering on the edge of insolvency due to a decade of Sandinista misrule. Beyond outright graft, the government used the pension system as a political tool, diverting money to programs that benefited Sandinista Party members but not the population as a whole. Ortega’s project was also harmed by the highhanded (and clearly unconstitutional process) that brought it about, with no stakeholder input or even a vote in his rubber-stamp congress. And younger Nicaraguans have long been reluctant to contribute to a pension system that is likely to fall apart before they reach an age to take advantage of it.

Ortega’s handling of the protests has only deepened his legitimacy problem. As elderly people, business owners and university students all began to protest, Ortega responded with violence and repression rather than compromise. He unleashed the Sandinista Youth — gangs of thugs associated with the ruling party, supported by the Nicaraguan police — on the protesters. The police have stood by as the auxiliaries attacked older protesters.

The heavy-handed response is one big reason the protests so quickly escalated, soon targeting much broader issues. Protesters now fill the streets chanting “Ortega y Somoza son la misma cosa” (Ortega and Somoza are the same thing), referring to the dictatorship overthrown by the Sandinistas and the Nicaraguan population in 1979. Pension reform was the catalyst for the biggest citizen revolt since the revolution 39 years ago, but it’s clear these protests have really been about authoritarianism all along.