" Which is to say, “You can’t shout ‘Fire!’ in a crowded theater” was first used to justify precisely the thing the First Amendment exists to prohibit: the official censorship of political speech by the state. Schenk was prosecuted under the Espionage Act for distributing a pamphlet containing nothing more controversial or subversive than an exhortation to “Assert Your Rights. "

― Kevin D. Williamson , The Smallest Minority: Independent Thinking in the Age of Mob Politics