Gramsci, that most (fatally) percipient early critic of the formation, structure and application of the theories of the modern hegemonic State, reasoned that hegemony would anticipate critics and therefore would also provide (supervised, controlled) space for criticism.
Cf: "Free Speech Zones."
Which speculation made me wonder (not for the first time) if the 'blogosphere,' especially, but pretty much the whole Internet-as-public-phenomenon thingee, is not a wonderfully Gramscian-hegemonic invention to authorize an outlet for more or less (and clearly atomized) "public dissent" which provides the appearance of actual accomplishment without there having to be any concomitant action.
As they say in that advert: "Brilliant!"
If I were an authoritarian cabal designing a social hierarchy, I'd want something like that in my operation. It's only when you don't know what your enemies are saying that those words become dangerous. (Wazzat Machiavelli say dat?)
This whole little slice of discourse underscores the adage: "Paranoids can have real enemies."