Banned Social Networks

People associate the Social Networks with freedom of expression and open access to information but now many countries have run out of patience with this freedoms examples of this can be:

                                                             

Mexico:The government has been thinking of banning Twitter because some people disclosing the location of police traps for drunk drivers  by writing "tweets".These messages alert drivers            where the police are lying in wait.
  
Russia:Youtube eventually has been banned by a Russian court in 2010 despite the fact that the president had a channel on the site.

Portsmouth and China:In those countries the autorities banned Facebook. In U.K they thing that their employees use the site and the managers don't know if users are loggin  during work hours.

There's  a lot of examples of why this Social Networks are banned but also I think that the main problem is the wrong use that the users give to them