In the mid-twentieth century, certain elements of the American popular music industry (publishers, recording companies, and broadcasters) began to redefine their product as something more than mere entertainment. This became evident in the arguments made by competing sides in a series of clashes that unfolded during that period, starting with the ASCAP-Radio dispute of 1941 and ending with the payola scandal in 1959. Although these disputes typically revolved around economic issues, in making their cases to the public the respective sides often asserted the significant role played by popular music in promoting core national values. While such rhetoric was basically self-serving, when set against the backdrop of major events like World War II, the Civil Rights Movement, and the Cold War, it resonated strongly with the public and helped convince many that popular music offered more to its audience than momentary diversion. Considering that the resolutions to these conflicts also tended to expand opportunities for previously marginalized styles and performers, notably African-Americans and rural southerners, it became natural to link popular music to ideas of social progress as well. This contributed to the creation of what could be called "rock and roll culture," a coherent set of values related to concepts of youth, authenticity, sexual liberation, and social equality that emerged by the end of the 1950s. These traits became a prevalent part of American culture through the end of the twentieth century, with popular music seen a perhaps the most significant medium for expressing those values.