How do media systems come to be structured in different ways? Through a comparative historical institutional analysis of the origins of broadcasting policy in the United States and Great Britain in the early twentieth century, this study examines reasons private, commercial interests dominated the U.S. system while Britain granted a monopoly to the publicly funded, noncommercial BBC. Policy outcomes at this critical juncture were contingent on different path-dependent notions of the public interest as well as temporal sequencing. Through an analysis of primary documents and secondary literature, this study considers the implications of these different approaches for modern communication policy and democratic society.