SWAT teams and angry protesters have clashed in a small St. Louis suburb following the death of unarmed black teenager Michael Brown. The eruption of protests and violence has been a long time coming. While I certainly do not condone rioting, examining the conditions surrounding Brown's death — and the deaths of several other unarmed black men killed by law enforcement recently — makes clear that community reactions like those in Ferguson, Mo., are bound to happen. America has continued to isolate poor black people in economically depressed neighborhoods under increasingly oppressive police tactics that breed distrust and hostility.

Ferguson has suffered from "white flight" in recent years, leaving pockets of structural poverty and deeply alienated black people. The once predominantly white suburb now is 65 percent black. Poverty afflicts 22 percent of residents, twice as many as in 2000.

Ferguson's story isn't uncommon in the United States. Authorities often see fit to heavily police towns with growing black and poor populations, to surveil them and occasionally to harass them in the name of a "broken windows theory" of policing, banking on such methods to control crime. The theory, promulgated by James Q. Wilson, holds that where there is urban disarray, there is crime. Wilson argued that cleaning up trash and fixing broken windows — but also quickly policing deviants and miscreants for even small-scale crimes — would lessen crime overall. The thinking was that by taking care of the small stuff, you won't face as much big stuff.

The theory caught on, and authorities began to use it all over the country. For example, Mayor Rudolph Giuliani and police commissioner Bill Bratton employed this theory in New York City during Giuliani's tenure, and it seemed to reduce crime. But increased "stop and frisk" tactics — which allow officers routinely to stop sometimes law-abiding citizens in search of illegal drugs, firearms or other criminal possessions — resulted in ever greater tension between communities of color and police, and in ever larger numbers of minority men being incarcerated.

The use of "broken windows" policing meant, in practice, increasing harassment of young black men. New York's use of stop-and-frisk is most commonly exercised against young blacks and Latinos. A recent report by the Center for Constitutional Rights found that black and Latino people are stopped much more frequently than whites under this program, even in mixed and especially in predominantly white communities. Further, the report noted, "Blacks and Latinos are treated more harshly than whites, being more likely to be arrested instead of given a summons when compared to white people accused of the same crimes, and are also more likely to have force used against them by police."

The racial biases underlying this disparity extend to other forms of aggressive policing, causing black people to associate police officers with humiliation and injustice, and stirring distrust for police in black communities around the country.

The intensified police presence in poor black communities fosters this negative association in residents from a young age. As children, they see police officers walk the hallways of their schools as in a prison. When black boys are involved in an altercation or disruption, instead of being sent to the principal's office, they are too often handcuffed on the spot and given a criminal record. Experience teaches black men that police officers exist not to protect them, but to criminalize and humiliate them. Few black boys get through adolescence without a story of police harassment, and with age, their stories proliferate. Black men engaged in innocuous activities — walking home from a corner store, holding a BB gun at Wal-Mart, leaving a bachelor party — become targeted as criminals by authorities. With each negative encounter, black men build up antagonism toward law enforcement. They develop defense mechanisms and toughen up to protect their pride and perceived respectability. With this built-up hostility, interactions over minor offenses, like suspicion of selling loose cigarettes, become quickly charged.

While this is not the first time in history that aggressive police tactics have plagued black communities, this generation of young people has limited tolerance for such experiments in policing at its expense. Compared with their grandparents, those in the millennial generation, regardless of race, are less inclined to blindly respect and trust authority. A 2011 MTV poll found that 70 percent of millennial respondents believed they could "successfully negotiate anything with authority figures." Further, a Pew Research poll found that millennials are detached from hierarchal institutions and are distrustful of people in general. This generation isn't intimidated by authority. On top of that, images of police brutality against black men have proliferated online, turning what might have been isolated local antagonisms into national grievances.

Under authoritarian oversight and normalized police harassment, a generation of young people were bound to get fed up and respond with the defiance and turmoil we are witnessing in Ferguson. Clearly, the relationship between the police and the communities they are charged with "protecting and defending" needs to change.

Elijah Anderson is a professor of sociology at Yale University. He wrote this article for the Washington Post.