For all those who thought the Ralph Northam story couldn’t possibly get worse, the Virginia governor’s “apology” may turn out to be more toxic than the original offense.

Let us stipulate that a healthier political culture might recognize that offense—a photo on his 1984 med-school yearbook page featuring a man in blackface next to a man in a Ku Klux Klan hood and robes—as simply a bad college moment. Certainly some already must. A Washington Post-Schar School poll released Saturday, for example, reports 58% of Virginia’s African-Americans...