Which World War II-era advertising campaign was so successful that it continued for over 70 years and transformed how companies maintained brand presence during wartime production shortages?

The history of advertising has seen numerous groundbreaking campaigns that changed how products were marketed forever. From traditional print media to the digital revolution, advertising techniques have evolved dramatically over the centuries. This trivia question focuses on a pivotal moment in advertising history that transformed how companies approached marketing and created brand loyalty during a critical period in American history.

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M&M's "Melts in your mouth, not in your hands" campaign (launched because the candy was sold to soldiers in tropical climates)
Coca-Cola's "I'd like to buy the world a Coke" global unity message
De Beers' "A diamond is forever" campaign (which created the tradition of diamond engagement rings)
Rosie the Riveter's "We Can Do It!" campaign for civilian factory recruitment