How does American pop culture's universalization lead to cultural homogenization?

Homogenization is a result of mass communication that ends the isolation of small communities. A person's culture is related to social context; we pick up culture from the people around us. Prior to large scale communication, initially through radio followed by television and the internet, local communities developed their own cultures. For example, in 19th century London, accents differed enough by community that one could pinpoint where a person came from in the city by...

Homogenization is a result of mass communication that ends the isolation of small communities. A person's culture is related to social context; we pick up culture from the people around us. Prior to large scale communication, initially through radio followed by television and the internet, local communities developed their own cultures. For example, in 19th century London, accents differed enough by community that one could pinpoint where a person came from in the city by the way they spoke. Likewise, in Appalachia, banjo styles differed from one county to another. 

When radios spread across communities during the early part of the twentieth century, two things happened. First is that exposure to a larger scale culture altered people's habits in general. Second, many people believed that whatever was on the radio was better than local, home-made ways of doing things; this set of beliefs hastened the demise of some of the old culture. In Appalachia, prior to the advent of radio, older people sang ballads that had been handed down for hundreds of years. After radio came into being, people grew up with early country music, such as the Carter Family, instead of the old ballads. 

This process is continuing in the twenty-first century with more and more media owned by fewer and fewer corporations. For example, radio shows may be produced at the national level by a corporation distributed at the local level. Instead of hearing local DJs, listeners hear the music choices of small group of people. News corporations have become larger and have swallowed up smaller organizations. Entertainment conglomerates have replaced smaller groups of people. The result is that fewer ideas (whether musical, cultural, or other forms) become available to people and local culture is replaced by homogenized nationalized versions of music, news, speech, and so forth.