“I’m going to clean up Chicago. I’m going to clean up Washington. I’m going to clean up Los Angeles.” With those words, President Trump has made crime not just a local concern, but a national campaign theme. The president has already sent National Guard troops into several Democratic-led cities. His message is clear: if cities can’t police themselves, Washington will do it for them.
But what often gets lost in this new law-and-order push is that violent crime doesn’t only endanger lives and property. It changes how people think about one another — and, over time, how democracy itself functions.
When trust erodes, so does civic life.
In a recent study of mine “Does Experiencing Violent Crimes Matter for Social Capital and Political Behavior?” I document how living through high levels of violent crime — even without being a direct victim — leaves lasting scars on how people relate to others. It makes us less likely to believe in our fellow citizens, less likely to join civic or political groups, and more likely to feel that we’re on our own. It also tends to push political preferences toward parties that promise security above all else.
The hidden cost of crime
Violent crime doesn’t just leave behind police tape and traumatized families. It produces something harder to measure — a world where people begin to assume that every interaction carries risk. Walking your dog at night or taking your children to the playground suddenly feels uncertain. Those fears come with economic and social costs: fewer partnerships, less community investment, fewer friendships and mentorships across neighborhoods, and an erosion of the civic spirit that keeps a city together.
Social scientists call this “social capital.” It’s the glue of community life — trust, mutual support and participation. Economists have shown that cities with strong social capital grow faster and adapt better to change. Political scientists find that trust fuels civic engagement, from voting to volunteering. When fear and suspicion replace it, people withdraw.
The long shadow of violence
My research tracks what happens to people who grow up amid violence, especially during their “impressionable years” between ages 16 and 25 — the period when values and social attitudes take shape. By linking more than 50 years of FBI crime data with tens of thousands of responses to the General Social Survey, I was able to compare people who came of age in high-crime environments with those who did not.
The differences are striking. A one-standard-deviation increase in violent crime at age 18 — roughly the gap between a city in turmoil and one at peace — makes young people 4 percentage points less likely to believe that “most people can be trusted.” They are more likely to think others will “take advantage of them,” and less likely to see people as “generally helpful.”
Politically, the effects are even larger. Those who grew up surrounded by violence are about 20 percent less likely to join a political club and 6 percent less likely to affiliate with the Democratic Party. The damage persists for decades, long after the crime wave itself has subsided.
This helps explain why surges in crime can produce long-term political shifts — and why national leaders who promise to “clean up” cities often find a receptive audience. Fear doesn’t just change voting behavior; it rewires how citizens see the social contract.
Why this matters for cities — and the nation
Major cities have struggled with violent incidents and public perceptions of disorder. But sending in troops won’t restore what violence has already taken: trust.
When people believe that no one — not neighbors, not government — can be trusted, civic life decays. Neighborhood associations collapse. Volunteer networks dry up. People stop showing up to meetings or polls. And once mistrust sets in, it feeds on itself, making future cooperation even harder.
That’s the hidden risk in turning the country’s urban crisis into a political spectacle. Deploying the National Guard may calm tensions briefly, but it doesn’t heal the civic wounds crime inflicts. What cities truly need is investment in community trust: mentoring programs, local associations, and opportunities that give teenagers a sense that their participation matters.
Restoring safety is essential. But so is rebuilding faith — in each other and in the idea that democracy still works. Because when trust fades, people don’t just avoid eye contact. They stop believing that collective problems can be solved.
And that is a loss no city, Democratic or Republican, can afford.
Ugo Troiano is an associate professor of economics at the University of California, Riverside. You can follow his Substack: utroiano.substack.com