Sen. Bernie Sanders, the Democratic candidate for president, shocked people when he noted that 51 percent of African-Americans aged 17 through 20 who have graduated high school or dropped out of high school are unemployed.

PolitiFact.com confirmed the statement as “mostly true,” suggesting that the numbers might even be worse than Sanders suggested.

This level of unemployment is a death sentence for a generation — representing for too many the dying of hope, of potential and even, in an age of mass incarceration, of freedom.

The figure is shocking, but the reality cannot be denied. For all the progress we have made on race in this country, there is still a stark difference between black and white poverty. As Emily Badger reports in the Washington Post, “The poverty that poor African-Americans experience is often different from the poverty of poor whites.” A poor black family is much more likely to live in an impoverished neighborhood. The concentrated poverty, as Badger writes, “extends out the door of a family’s home and occupies the entire neighborhood around it, touching the streets, the schools, the grocery stores.”

A new report on the “Architecture of Segregation” by Paul Jargowsky for the New Century Foundation details the stark differences that exist in cities across the country. In metropolitan Chicago, for example, more than one in three poor African-Americans live in what are called high-poverty census tracts (neighborhoods where the poverty rate is above 40 percent). That is 10 times the rate for poor whites. And it has gotten worse, not better, in cities across the country over the course of this century.

Separate and impoverished. We know the effects. Infants suffer bad nutrition, grow up surrounded by lead paint. Children navigate mean streets to go to impoverished schools. They lack after-school and summer programs. Families break apart. Guns and drugs come in; jobs go out. There’s no affordable transportation to get to where the jobs are. Houses are abandoned. Hospitals close. Decent grocery stores are nowhere to be found.

As Jargowsky says, this isn’t really an accident. It is the product of systemic discrimination, of zoning laws that shield off wealthy areas from the poor, of public housing that is concentrated in a few neighborhoods. Isolation in poor neighborhoods is an imposition, not a choice.

This could be different. In London, for example, every region must have some social housing for poor and working class people. Imagine if every suburb were required to provide a proportionate amount of housing for the poor and the lower-wage workers. Suddenly the poor would have access to better schools, better health care, safer streets, more role models and healthier (and less expensive) food stores.

This takes a plan, a plan that will meet great resistance. Dozens of Chicago’s wealthy suburbs, Badger notes, have ignored state deadlines to produce affordable housing plans.

Poor African-Americans are penned up, in poor neighborhoods and too often literally in jails and prisons. This is an imposition, not a fate, a policy choice that is morally indefensible and socially explosive.