In this joke ad for some brand of American cheese, the announcer would claim that any cheese that is not American Cheese is, in fact, Un-American Cheese, if not outright Anti-American Cheese, and anyone who eats it is a traitor and an enemy of freedom. And to show how serious this threat of cheesy treason is, we see a new Congressional committee, the House Un-American Cheese Activities Committee, and they grill American citizens over eating non-American cheeses, demanding they name the names of other Un-American cheeses that either they have, or they’ve seen other people, eat. And so the committee serves to intimidate everyone into eating only patriotic, liberty-flavored American cheese!
(This is the only way I can think of to get most of the adults I know to be willing to eat American cheese: threaten them with charges of treason and accuse them of being unpatriotic in their cheese-related activities. But their kids just love American cheese.)
