The nation has made great progress in race relations in the last 50 years. But in some respects, we’ve gone backwards, and we continue to do so.

A case in point is a Wednesday interview with U.S. Secretary of Education Arne Duncan on NPR’s Diane Rehm Show.

Host Susan Page asked the secretary about his views on racial integration. I was a panelist on the program, and was asked to comment.

Ms. Page’s specific question concerned a lawsuit in Louisiana. This is what Secretary Duncan said about the broader issue of racial integration:

“I fundamentally think the need for integration and more integrative schools is very real, and there are things that we can do. Obviously, there are housing patterns that present challenges.… But I was fortunate to go to an integrated school, you know, all the way through K-12.

And I don’t think I could do a job like this was I not, you know, didn’t have that kind of opportunity. And far too many children today are denied that opportunity. So, yes, we want to do everything to make sure they’re, you know, getting rigorous course work and have great teachers and are academically prepared for college. But you want children to grow up comfortable and confident with other people who come from different backgrounds from them.

And if they don’t have those opportunities—not that you can’t learn it as an adult, but it’s much harder. So whatever we can do to continue to increase integration in a voluntary way—I don’t think you could force these kinds of things—we want to be very, very thoughtful and to try to do more in that area quite frankly.”

It was a shocking statement in two respects, but typical of how even many liberals who claim to support racial justice today think of integration.

First, Secretary Duncan supports integration because it enables children to “grow up comfortable and confident with other people who come from different backgrounds.” This is the “diversity” argument for integration, initially promoted by the U.S. Supreme Court in its 1978 Bakke (University of California, Davis, medical school admissions) decision and subsequently enshrined in its 2003 Grutter (University of Michigan law school admissions) and recent 2013 Fisher (University of Texas undergraduate admission) decisions. These court opinions mostly justified integration because it benefits white elites. As briefs by major corporations and the military explained in Grutter, it will be harder for commanders and executives to manage diverse workforces if these leaders had not been exposed to minority students in school. The briefs also argued that black leaders should have had experiences in school getting along with whites, and it would also be beneficial if soldiers and employees were comfortable in their units with others of different racial and cultural backgrounds. This is the theory of integration to which Secretary Duncan subscribes.

Indeed, Secretary Duncan’s first reaction to the question was to say that having gone to an integrated school makes it easier for him to lead U.S. education policy. As the Grutter briefs argued, integration is important mostly because diversity benefits the white managerial class.

But this is not the most important reason why school racial integration is imperative. Integration is necessary for the success of black students, even if they never have the opportunity to command white soldiers or hold jobs in predominantly white enterprises. When African-American students from impoverished families are concentrated together in racially isolated schools, in racially isolated neighborhoods, exposed only to other students who also come from low-income, crime-ridden neighborhoods and from homes where parents have low educational levels themselves, the obstacles to these students’ success are most often overwhelming. In racially isolated schools with concentrations of children from low-income families, students have no models of higher academic achievement, teachers must pitch instruction to a lower academic average, more time is spent on discipline and less on instruction, and the curriculum is disrupted by continual movement in and out of classrooms by children whose housing is unstable.

Social science research for a half century has documented the benefits of racial integration for black student achievement, with no corresponding harm to whites. When low income black students attend integrated schools that are mostly populated by middle class white students, achievement improves and the test score gap narrows. By offering only a “diversity” rationale for racial integration, Secretary Duncan indicated that he is either unfamiliar with this research or chooses to ignore it.

His response was especially troubling because the segregation of black students is increasing, not decreasing. In 1970, the typical black student attended a school that was 32 percent white. By 2010 it had fallen to 29 percent. The typical black student still attends a school that is majority low-income. In places where black student achievement is most in crisis, the numbers are much worse. In Detroit, for example, in 2000 (the most recent year for which such data have been calculated) the typical black student attended a school where 2 percent of students were white, and 85 percent were low income.

Secretary Duncan’s comment on integration was even more shocking for another reason. He stated that we should “increase integration in a voluntary way—I don’t think you could force these kinds of things.” Secretary Duncan is young (only 48 years old) and may not realize that in 20th century discussions of integration, “voluntary” was a code word for massive resistance to desegregation, and saying you can’t “force these kind of things” was the most common rationale for maintenance of black subjugation. We have just celebrated the 50th anniversary of the March on Washington and are about to celebrate the 50th anniversary of the 1964 Civil Rights Act that the March promoted. The argument that Lyndon Johnson confronted most frequently when he pressed for passage of the Civil Rights Act was that segregation resulted from racial prejudice and that change could only come from a change, as it was said, “in men’s hearts.” Johnson was, segregationists claimed, trying to “move too fast” by trying to force these kinds of things.

Of course, ultimately racial integration must be “voluntary.” Nobody proposes picking up black families and forcibly depositing them in white suburbs. But no education secretary has been as deft as Arne Duncan in creating incentives—both carrots and sticks—to get states to follow his favored policies that are technically voluntary. There are, for example, laws prohibiting the federal government from mandating national curriculum standards. States can only sign on to Secretary Duncan’s preferred standards (called the “Common Core”) voluntarily. But this has not prevented him from conditioning waivers from the most unworkable aspects of the No Child Left Behind law on states’ agreement to adopt the Common Core standards. The federal government has no authority to require states to evaluate teachers based on their students’ test scores. States can only adopt such policies voluntarily. But this has not prevented the secretary, in his Race to the Top program, from awarding desperately needed federal stimulus funds during the depths of the recent recession to states conditioned in part on states’ willingness to move towards evaluating teachers based on student test scores. In other areas as well—early childhood education and after-school programs, for example—Secretary Duncan has tried to force these kinds of things by using federal funds to get states and districts to adopt policies he favors.

But not in the case of racial integration. Only in this area, apparently, does Secretary Duncan believe that progress must be entirely voluntary, unforced by carrots and sticks, and he has ignored opportunities to promote racial integration. Many states, for example, permit all-white suburbs to maintain zoning ordinances that exclude low- and moderate-income housing. State legislation to prohibit such ordinances could have been rewarded in Race to the Top funding competitions, or in waiver grants for No Child Left Behind requirements. Other states permit landlords to refuse to rent to families who benefit from the federal housing voucher program, resulting in low income families’ concentration only in low-income communities. Banning such discrimination could also have been a condition of federal education funds or NCLB waivers. Adoption of such “voluntary” policies could make a contribution to narrowing the academic achievement gap that is so much a focus of Secretary Duncan’s rhetoric.

It is hard to fault Secretary Duncan too much for thinking that integration is desirable only because it is good for students to experience diversity, or thinking that unlike so many other policies, integration can’t be “forced.” His views on racial matters only reflect conventional thinking, including that of most liberal policymakers. As a society, much as we celebrate the achievements of the civil rights movement 50 years ago, we have abandoned racial integration as a goal and not only maintain segregation but have taken steps towards re-segregating children and communities. That is why the Economic Policy Institute has published a series of papers on the Unfinished March, describing how the goals of the March on Washington have been unfulfilled, in education and other policy areas, and what we can and should do to fulfill them.