As I watched recent news video of young Chileans joining protests touched off by a subway fare increase, setting fires and chanting slogans against rich elites, my first thought was how lucky they were.

More than a third of the prosperous South American country’s 19 million citizens are younger than 30, which means they were born and raised in a period of benign civilian government. They have no memory of the brutal military dictatorship that ruled from 1973 to 1990 with messianic fervor and iron-fisted repression, after overthrowing an elected socialist president.

They never knew real fear, the kind that comes when a man is dragged screaming into an unmarked vehicle while passersby look on silently in horror and shame. They never experienced the implacable power of a professional military institution determined to quash all dissidence, employing humiliating forms of torture and leaving more than 3,000 detained leftists missing forever.

They never experienced the surge of astonishment and tearful joy that greeted the country’s first crucial step toward liberation, one chilly night in October 1988, after a national yes-no plebiscite in which voters rejected extending Gen. Augusto Pinochet’s rule. After several tense hours, filled with rumors of a second coup, the military junta said it would accept the results.

I was there that unforgettable night, scribbling notes and mingling with exultant throngs that poured into the streets of Chile’s capital, Santiago, chanting, dancing and hugging discomfited police officers. As the swirl of emotion flowed around me, I felt that Chile — a country once described as so civilized that any problem could be solved over a glass of good cabernet — had regained its soul.

I had also been there repeatedly during the waning years of military rule, first covering the story for the Boston Globe and later working on a book. Political repression had eased, partly under international pressure, but harsh economic austerity measures, imposed by fiat, had cost thousands of public servants their jobs, pensions and dignity. People skilled in the trades were reduced to selling toys on the sidewalk.

One man, a jobless carpenter, wept as he told me he had been forced to sell off his cherished tools and his wife’s wedding ring.

Those hardships, coupled with a growing student movement, spawned protests in the capital that were repeatedly met with tear gas and water cannons. Years later, I vividly remember the acrid, burning sensation in my sinuses as I scrambled to flee the clouds of noxious gas, tears streaming down my face.

To the end, Pinochet enjoyed staunch support among the upper classes that had once welcomed the coup as a necessary antidote to the threat of a Cuba-inspired leftist uprising, and the yes option for extending his rule won a sizable number of votes. But after 17 years, most Chileans had had enough of hating one another and saluting the generals. On Oct. 5, 1988, the no option prevailed, 54 percent to 43 percent.

During a postmortem gathering at a conservative Santiago think tank, its director, Arturo Fontaine, told his gloomy audience, “We cannot keep fighting phantoms that are no longer in people’s minds.” The plebiscite, he said, had been a “great secular communion.”

Then he added a quote from Aristotle: “For the state to endure, it needs more than commerce and security. It needs civic fraternity.”

By 1990, a centrist civilian president had been elected, former political prisoners were back in public life, and Pinochet had accepted a respectable sinecure as “Senator for life.” He remained a pariah among international human rights groups, but in other circles, he received praise for transforming a bloated, state-centered economy into an efficient, pro-business one — something an elected leader could not have easily imposed. He died in 2006, at 91.

Chile was soon being touted as a role model for Latin American development, though this success had come at a bitter human cost. In the decades since then, this reputation solidified, and Chile’s economic dynamism continued through several election cycles that saw left- and right-leaning leaders win alternating four-year turns in power.

The current president, Sebastián Piñera, is a conservative, Harvard-trained economist and businessman who has won office twice and made a fortune introducing the first credit card to Chile. In 2011, during his first term, he faced massive protests by students demanding educational reforms, while Chile’s growth slowed and severe economic inequality persisted.

This month, a new, more violent bout of street demonstrations erupted, ignited by young people protesting a 4-cent fare increase for the capital’s subway system. On Oct. 19, Piñera suspended that action, but the protests intensified, with buildings set on fire and markets looted. Riot police battled protesters, and three people died in the mayhem.

Taken aback by the escalating crisis, the president declared a state of emergency in Santiago and sent in an army general to restore order. A curfew was declared, and for the first time in nearly three decades, security forces patrolled the streets. By week’s end, 19 people had been reported killed in the growing turmoil.

The president, mindful of the ominous optics, sought to calm the demonstrators, saying, “I have listened with humility and great attention to the voice of my compatriots.”

Under Pinochet, there would have been no such appeasement, and the protests would have been quashed without restraint. The protesters who took to the streets in the name of economic justice had history on their side, reining in any authoritarian impulse to crack down hard.

Yet the current unrest is about far more than a subway fare increase, and it is starting to swell and diversify.

On Friday, hundreds of thousands of people peacefully filled a vast plaza in Santiago, demanding relief as basic costs have kept rising for the poor in one of Latin America’s wealthiest countries. Elsewhere, truck drivers staged slowdown strikes, and crowds tried to force their way into the national parliament building, where police responded with tear gas.

Piñera, who could be forced to resign if the crisis continues to escalate, tweeted reassuringly late Friday, “We’ve all heard this message. We’ve all changed.” His administration quickly announced increases in minimum wages and public pensions and the freezing of a planned increase in electricity rates.

But it may take more than short-term palliatives to satisfy the growing public anger in Chile, a democracy that has restored political freedom but failed to meet rising expectations of economic fairness. The young protesters never knew the intimidating power of military dictatorship — and many of those old enough to remember now feel emboldened to join them.