Jonathan Zimmerman teaches history and education at New York University.

Let’s try one of those word-association games you used to play as a kid. If I say “racial integration of schools,” who comes to mind?

If you’re like most of us, you conjured figures from the past. Perhaps you thought of the heroic young African Americans who desegregated all-white schools in places such as Little Rock and New Orleans in the 1950s and 1960s. Or maybe Earl Warren, author of the 1954 Brown v. Board of Education decision barring schools from separating students on the basis of race.

I doubt you chose anyone from contemporary American life. Our schools are more segregated than at any time since the late 1960s, but you probably can’t name a national political figure today who has insisted — loudly, clearly and consistently — that kids of different races should be in the same classrooms.

That’s about to change. The incoming secretary of education, John B. King Jr., has been a forceful advocate for integrating American schools. This month, President Obama tapped King to replace Arne Duncan, who focused less on integrating the races than on closing the “achievement gap” between them.

That’s been a dominant theme of education reform since the passage of the 2001 No Child Left Behind Act, which requires schools to report test scores by race; if one of its racial groups is not making progress, an otherwise successful school can face penalties under the law. But NCLB makes no reference to integration at all. The goal is to bring up the test scores of every race, not to bring the races together into the same schools.

Meanwhile, the Supreme Court has restricted the ability of school districts to promote racial integration. Striking down desegregation plans in Louisville and Seattle in 2007, the court questioned whether integration would enhance minority achievement. “It is far from apparent that coerced racial mixing has any education benefits,” wrote Justice Clarence Thomas, the lone African American on the court, “much less that integration is necessary to black achievement.”

Do black children have to attend an integrated school to succeed? Of course not. But we do have strong evidence that they are more likely to succeed if they go to school with other races.

Just last month, an Education Department study showed that African American eighth-graders who attended schools that were more than 60 percent black scored significantly lower on standardized math tests than African Americans of similar backgrounds who attended integrated schools.

Other research has shown that black kids in integrated schools enjoy higher earnings and rates of employment later in life; they’re also less likely to bear children as teenagers, or to be incarcerated as adults. But you don’t hear many people — of any race — talking about that.

Whites fear that racial integration will hold back their children academically, even though studies have repeatedly shown otherwise. And blacks worry that campaigns to integrate schools demean African Americans, as Thomas complained in an earlier opinion. “It never ceases to amaze me that the courts are so willing to assume that anything that is predominantly black must be inferior,” Thomas wrote in 1995, voiding a court-ordered Kansas City, Mo., program that sought to draw white children back into the public schools.

Enter King. As education commissioner in New York state, he earned a good deal of negative press — and the enmity of the teachers union — for his embrace of the Common Core standards and of a new teacher evaluation system based partly on student test scores. Fewer people noticed King’s “socioeconomic integration” project, which provided grants to increase diversity in high-poverty school districts.

Significantly, King cast the project as a way to improve minority academic achievement. “Diverse schools create important educational opportunities,” King said, announcing the program last year. “Our students shouldn’t be isolated because they come from struggling neighborhoods.”

He’s right. Under No Child Left Behind, we have pretended that we can close the racial achievement gap without integrating the races. But that’s a fool’s errand, born of a separate-but-equal fantasy that Brown v. Board of Education never fully dispelled.

So kudos to Obama — himself the product of richly integrated schools — for appointing King. And congratulations to King for speaking some hard truths that too many Americans — of every race — would prefer not to hear. No matter what you think of King’s other reform priorities, his commitment to integration is right on target. Anything less will be wrong for the United States, especially for the least fortunate among us.