In the more than two years since gun violence suddenly began to rise in cities all across the country, researchers have been asked repeatedly to explain what caused the rapid increase and what can be done to reverse it. The urgency behind the question is warranted: Gun homicides rose by 34 percent from 2019 to 2020, and then rose again in 2021. In Chicago alone, over 250 more people were murdered in 2020 than in 2019, and that heightened level of violence continued into 2021. Murders are down slightly this year in Chicago and many other cities, but young lives continue to be lost to gun violence at a much higher rate than just a few years ago.

The immediate crisis is clear. But these short-term trends can sometimes distract us from the question of how American cities got to this point, and how they can move toward a sustained period of low violence. To answer these questions, a long view can be useful.

My colleague Alisabeth Marsteller and I recently analyzed data on violence in Chicago’s neighborhoods over nearly six decades, from 1965 through 2020. Chicago is not close to the most violent city in the United States, but it is the only city with data available to track murder in individual neighborhoods over such a long time frame. This view reveals a remarkable pattern: The level of violence in the city has risen and fallen sharply over the past half century, but the distribution of violence has not changed significantly. The group of neighborhoods on the West and South Sides that had the highest level of violence in the late 1960s have continued to have the highest level of violence in every single period since.

This rigid geography of violence, which has persisted even as the city’s economy has changed and new populations have moved into and out of these neighborhoods, raises a question that should be considered alongside the more immediate question of why violence is rising or falling in a particular place at a particular time: Why are some American neighborhoods so vulnerable to so much violence?

To answer this question requires thinking less in terms of months and years, and more in terms of decades. It requires thinking less about specific neighborhoods and cities where violence is common, and more about larger metropolitan areas where inequality is extreme and the affluent live separated from the poor. And it requires thinking less about individual criminals and victims, and more about bigger social forces, including demographic shifts, changes in urban labor markets, and social policies implemented by states and the federal government. All told, nearly six decades of data on violence in Chicago’s neighborhoods point to an unmistakable conclusion: Producing a sustained reduction in violence may not be possible without addressing extreme, persistent segregation by race, ethnicity, and income.

If this all seems far removed from the people wielding guns in cities like Chicago; Portland, Oregon; and Philadelphia, it is. The forces that have left American neighborhoods vulnerable to rising violence are entirely distinct from the people who live in those neighborhoods.