The Myth of Natural Monopoly

Professor Thomas DiLorenzo quotes economist Harold Demsetz bursting the myth of monopoly :

Six electric light companies were organized in the one year of 1887 in New York City. Forty-five electric light enterprises had the legal right to operate in Chicago in 1907. Prior to 1895, Duluth, Minnesota, was served by five electric lighting companies, and Scranton, Pennsylvania, had four in 1906. … During the latter part of the 19th century, competition was the usual situation in the gas industry in this country. Before 1884, six competing companies were operating in New York City … competition was common and especially persistent in the telephone industry … Baltimore, Chicago, Cleveland, Columbus, Detroit, Kansas City, Minneapolis, Philadelphia, Pittsburgh, and St. Louis, among the larger cities, had at least two telephone services in 1905.

There's no such thing as a "natural monopoly" , it's only the invention of politicians limiting supply.