If standards and curricula seem balanced and fair, does that mean that subversives have done a good job of disguising their sneaky ideological poison? That has long been the accusation of conservative intellectuals. Leftist academics, conservatives have charged for decades, make their work seem neutral, while really injecting a biased and enervating leftism.

We see this tradition alive and well in conservatives’ recent attack on the teaching of US History. As I noted in an essay in History News Network, Dinesh D’Souza’s new film warns that leftist teachers have taught America’s kids to hate America.

Other conservative intellectuals take a similarly skeptical view of the new curriculum for Advanced Placement US History. Peter Wood of the conservative National Association of Scholars accused the new APUSH curriculum of insisting on a “worldview that emphasizes America as a place of European conquest, economic exploitation, and the struggle for basic rights against the power of the privileged.” Similarly, conservative activists Jane Robbins and Larry Krieger have warned that the new APUSH curriculum peddles a “consistently negative view of the nation’s past.”

Wood, especially, has offered examples of the sorts of negative attitude he critiques. One of the subtopics for the early period, Wood points out, depicts European settlers as devilish racists:

Reinforced by a strong belief in British racial and cultural superiority, the British system enslaved black people in perpetuity, altered African gender and kinship relationships in the colonies, and was one factor that led the British colonists into violent confrontation with native peoples.

But more important than the specific examples of egregious anti-American sentiments, Wood charges, is a more subtle attitude embedded within the curriculum. As he puts it, “Sometimes these concerns break out into overt emphasis but they are present throughout.”

Apparently unconsciously, these conservative critics are echoing a long tradition of conservative educational thinking. As I argue in my upcoming book, throughout the twentieth century conservatives warned that schools were being led in leftist directions, often by this same sort of sneaky subversion. The leftists were so sneaky, conservatives warned, that readers might not even notice their subversion.

In the 1939-1941 conservative campaign against Harold Rugg’s social-studies textbooks, for example, critics warned that unwary readers could be duped into thinking the books were balanced and fair. One coalition of conservative activists called the books’ leftism “extremely clever.” Instead of openly proclaiming their leftist bias, Rugg’s books led children “with gentle language and a pedagogic smile . . . through the successive stages of indoctrination.” These conservatives conceded that many readers might find nothing wrong with Rugg’s books. But that only meant, they warned, that the danger was that much greater.

This sort of obvious-only-to-the-initiated analysis of leftist bias seems a double-edged sword. On the one hand, it presents conservative intellectuals with a difficult task. They must convince readers that even seemingly balanced curricular material is secretly anti-American, secretly leftist. That’s a tall order. But when school subversion is embedded cunningly within seemingly neutral material, conservative intellectuals are able to explain why so many popular textbooks and curricula have prospered in spite of their leftist implications.

Are the new APUSH materials really biased? Try it. Read the new curriculum guide. Does it seem like a biased leftist document to you? Its makers didn’t think so. But does that prove that conservative intellectuals are paranoid? Or does it show, rather, that the educational establishment is so dominated by left-leaning academics that they don’t even notice their own bias?