Tucker Carlson huddled in a low-ceilinged dungeon that had served as a holding pen for Africans bound for enslavement in the United States. It was a July day in 2003 in Ghana, and Carlson stood alongside some of America’s most prominent civil rights leaders.

The conservative commentator, who at the time co-hosted the CNN show “Crossfire,” walked through the memorial, where a guide told how the shackled Africans who did not perish during the voyage were sold as human chattel in America.