A number of clever marketing strategies come to mind. Professional wrestling is a classic example of this appealing strategy. Hulk Hogan, Ric Flair and the Macho Man are either all good or all bad. Yes, they do, on occasion, become transformed, but only to their former polar opposites. Wrestling promotions and matches are presented as good versus evil.
Wrestling is successful for a number of reasons.
This is only one significant aspect of the success. Presidents appeal to the goodness of America as they seek support for their policies that will conquer an evil empire or purge a dictator. All are attempts, no matter how subtle or blatant, to sway and sell. And it sells. It really does.