When the new york times magazine published its 1619 Project in August, people lined up on the street in New York City to get copies. Since then, the project—a historical analysis of how slavery shaped American political, social, and economic institutions—has spawned a podcast, a high-school curriculum, and an upcoming book. For Nikole Hannah-Jones, the reporter who conceived of the project, the response has been deeply gratifying.

“They had not seen this type of demand for a print product of The New York Times, they said, since 2008, when people wanted copies of Obama’s historic presidency edition,” Hannah-Jones told me. “I know when I talk to people, they have said that they feel like they are understanding the architecture of their country in a way that they had not.”

U.S. history is often taught and popularly understood through the eyes of its great men, who are seen as either heroic or tragic figures in a global struggle for human freedom. The 1619 Project, named for the date of the first arrival of Africans on American soil, sought to place “the consequences of slavery and the contributions of black Americans at the very center of our national narrative.” Viewed from the perspective of those historically denied the rights enumerated in America’s founding documents, the story of the country’s great men necessarily looks very different.

In the age of social-media invective, a strongly worded letter might not seem particularly significant. But given the stature of the historians involved, the letter is a serious challenge to the credibility of the 1619 Project, which has drawn its share not just of admirers but also critics.

Nevertheless, some historians who declined to sign the letter wondered whether the letter was intended less to resolve factual disputes than to discredit laymen who had challenged an interpretation of American national identity that is cherished by liberals and conservatives alike.

“I think had any of the scholars who signed the letter contacted me or contacted the Times with concerns [before sending the letter], we would’ve taken those concerns very seriously,” Hannah-Jones said. “And instead there was kind of a campaign to kind of get people to sign on to a letter that was attempting really to discredit the entire project without having had a conversation.”