Around the world, 2019 has been a year of public protest, and in some countries it’s not hard to understand why. In Hong Kong, demonstrators want to preserve the city’s autonomy within a repressive Chinese political system. In Algeria and Sudan, the issue is frustration with decades of dictatorship. In Ecuador, Nicaragua and Haiti, it’s poverty and bad governance. In Iraq and Lebanon, the protest focus is endemic corruption.

But what’s going on in Chile, one of South America’s most peaceful and prosperous countries? Earlier in October, a team of government technocrats announced that a weakening currency and higher fuel costs demanded an increase from 800 to 830 pesos in the cost of rush-hour public-transit fares in Santiago, Chile’s capital. That’s a rise of about 4 U.S. cents. In protest, younger commuters began dodging the fares, prompting a police crackdown and a wave of arrests.

The public anger, and the protests, then boiled over. Demonstrations spread to other cities, and some turned violent. Shops were looted, fires were set, and the government declared a state of emergency. Curfews were established in the country’s largest cities. Startled Chileans have seen nothing like this since the end of the Pinochet dictatorship nearly three decades ago, and President Sebastián Piñera seems slow to recognize the public anger as legitimate.

This surge of public fury didn’t come from nowhere. Chile’s new middle class has expectations for improving living standards. There have been protests in recent years over the cost and quality of education and health care and over pensions that don’t help the elderly make ends meet, but little has changed in response. There is also the reality that Chile has one of the widest gaps between rich and poor of all the Organisation for Economic Co-operation and Development countries. But to understand why Chile’s unrest is especially worrisome for other middle-income countries, look to the larger problem of unfairness.

In 2017, three Yale University scholars published a report in which they argued that concerns about inequality miss the mark. “There is no evidence,” they wrote, “that people are bothered by economic inequality itself. Rather, they are bothered by something that is often confounded with inequality: economic unfairness.” In other words, their study found that people will accept that some within society have more than others if they believe the better-off have earned their wealth and, crucially, if those less well-off have a fair chance to do better in the future.

That would mean Chileans, and those who live in other relatively peaceful and prosperous countries, are angered by doubts that the political system that governs their lives can provide a fair shot to get ahead. Why, they might ask, should poorer people who rely on public transit have to pay the price for a strong dollar and higher diesel costs? Particularly at a time when the wealth gap continues to grow. This is not a preference for one political party over another. It’s an explosion of anger at an entire system that some consider hopelessly rigged.

In that sense, Chile is a sign of protests to come in places where you might not expect to see unrest. Widening wealth gaps are a global phenomenon, and a future in which new technologies eliminate lower-skilled jobs and make life better for the highly educated is likely to widen the divide still further.

And though Chile’s government has backed down on the fare increases, the protests continue.

This appears in the November 04, 2019 issue of TIME.

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