Tyrants and Freedom of Expression
As David A. Strauss so cogently recognized, in his article, Persuasion, Autonomy, and Freedom of Expression, 91 Colum. L. Rev. 334, 337 (1991): "[T]yrants suppress speech because they fear it will be persuasive."
This fear explains some of the major developments in free speech history. For example, after Johannes Gutenburg invented the printing press in 1436, governments moved to suppress this new "technology" because people could use it to communicate more efficiently and effectively with each other. Prior to this invention, the people could communicate with each orally, but it was difficult to efficiently communicate with large audiences. The printing press changed the dynamic by allowing people to print multiple copies of texts and disseminate them widely.
At the same time, this "democratization" of technology struck fear into the heart of government which previously had exercised a semi-monopoly over the means of communication. In an attempt to address the potential "evils" that might result from unrestrained communication, governments enacted licensing laws (which prevented individuals from publishing without a license, and required that proposed texts be vetted through governmental censors), and England (in particular) enacted seditious libel laws (which made it a crime to criticize the government, and punished truthful communications more severely than untrue communications on the theory that they were more likely to have impact).