Did The U.S. Government Fostered monopoly or oligopoly ownership throughout radio's history. Why do you think this occurred, and how do you think that policy benefited or disadvantaged the development of radio?

Here are a number of excellent sites on the History of Radio.

http://www.google.com/search?hl=en&ie=ISO-8859-1&q=History+of+radio&btnG=Google+Search