(Chris Ramirez | The New York Times) Visitors view “Pickett’s Charge” in the Gettysburg Cyclorama, at the Gettysburg National Military Park in Gettysburg, Pa., on Nov. 7, 2005. "The debate over how American schools should teach about race and racial history has reached a curious juncture, in which it’s becoming hard to tell what the argument is about," writes New York Times opinion columnist Ross Douthat.