Michael Kinsley once defined a gaffe as when a politician accidentally tells the truth. If this has come to be known as a “Kinsley gaffe,” perhaps it should be called a “Harris gaffe” when a stage-managed politician accidentally reveals her plans. In one of her rare unscripted media appearances, Kamala Harris told Wisconsin Public Radio that she supports ending the Senate filibuster in order to pass federal abortion legislation. “I think we should eliminate the filibuster for...