When President Trump summoned Lonnie Bunch, the secretary of the Smithsonian Institution, for lunch at the White House on August 28 of last year, Bunch’s advisers assumed that the end was near. Trump had spent months threatening the Smithsonian’s independence; just nine days earlier, he’d written on Truth Social that “the Smithsonian is OUT OF CONTROL, where everything discussed is how horrible our Country is, how bad Slavery was, and how unaccomplished the downtrodden have been.”It stood to be a tough visit, and not only because Bunch, the first Black leader of the Smithsonian, takes the widely held position that...