I think it is not real limitation per se. OK, there are real limitations, like the BBC censorship of comments on their website (they call it moderation). But mostly it is orwellian double-thinking occupying the mind of the average Westerner. Examples? Even after this photo - http://mars.jpl.nasa.gov/msl-raw-images/msss/00065/mhli/0065... a rare Westerner will allow himself to think there is no rover on Mars. It is self-censorship at almost pre-conscious level what horrifies me in the Western world.