In a long day in Mobile, Ala., on Thursday, Dr. Ben Carson struck all the right grace notes, creating as vivid a contrast with Donald Trump's histrionic August visit as could be imagined. Whereas Trump was all about himself, exhaustingly and boringly so, Carson maintained a relaxed and humble presence throughout the seven-event day -- winning with winsomeness rather than with boasting and bombast. But the day was not without controversy -- even if it was entirely media-created. A midday press conference created a stir when Carson, discussing the Syrian refugee issue, stressed that Americans should first make sure...