In 1973, "Keep on Truckin'," a phrase popularized by Robert Crumb's comic strip, became a symbol of perseverance and optimism in the United States. Accompanied by illustrations of striding figures, it embodied the era's spirit of resilience and carefree movement. The phrase, reflecting individual expression and motivational energy, was widely adopted on t-shirts and merchandise, representing determination and joy during the socio-economic challenges of the early 1970s.