David J. Bobb, director of the Hillsdale College Kirby Center for Constitutional Studies and Citizenship, in Washington, D.C., is author of "Humility: An Unlikely Biography of America's Greatest Virtue," forthcoming from Thomas Nelson.

Upon the death of the Marxist-inspired historian Howard Zinn in 2010, eulogies rang out from coast to coast calling him a heroic champion of the unsung masses. In Indiana, then-Gov. Mitch Daniels refused to join the chorus and instead sent emails to his staff wondering if the historian's "execrable" books were being force-fed to Hoosier students. The recent revelation of these emails provoked an angry backlash....

For Americans stuck in impoverished communities and failing schools, Zinn's devotion to history as a "political act" can seem appealing. He names villains (capitalists), condemns their misdeeds, and calls for action to redistribute wealth so that, eventually, all of the following material goods will be "free—to everyone: food, housing, health care, education, transportation." The study of history, Zinn taught, demands this sort of social justice....

While social-justice instruction may sound to some like it might be suited to conflict resolution, in practice it can end up creating more discord than it resolves. Several years ago, the Ann Arbor, Mich., public schools faced complaints from the parents of minority students that the American history curriculum was alienating their children. At a meeting of the district's social-studies department chairs, the superintendent thought that he had discovered the cure for the divisions plaguing the school system. Holding up a copy of "A People's History," he asked, "How many of you have heard of Howard Zinn?" The chairwoman of the social studies department at the district's largest school responded, "Oh, we're already using that."...