Remember the lectures from the Media Great and Good that Republicans and conservatives had to reject Senate candidate Roy Moore in Alabama last year to retain any sense of principle and self-respect? The sound you don’t hear this year is any comparable editorializing that Democrats and liberals should reject Bob Menendez in New Jersey.

Republican voters make mistakes, and Alabama conservatives did by nominating Judge Moore, who was credibly accused of courting minors when he was a young prosecutor. But most national conservatives...