Bucknell University, a well-regarded liberal arts institution set in a picturesque location in the rolling Pennsylvania countryside, looks entirely benign. Its campus is safe, its students intelligent. It counts among its alumni the famed author Philip Roth and Leslie Moonves, the president of CBS. It’s a college to which most parents would be proud to send their kids. But if your son or daughter is the type who might join the Bucknell University Conservatives Club (BUCC), you would be well-advised to send him or her somewhere else. Because Bucknell really, really does not want to hear what the students of...