I recommend the linked article-- it's a review of a book about the details and effects of social pressure to not express one's actual beliefs, including stability of generally unwanted social systems, and bloodless revolution when the beliefs change faster than the institutions.

See also Racial Paranoia, which describes the unintended consequence of the high cost of being overtly racist in the US-- it's impossible to know how racist any individual is, so people go nuts looking for clues about the level of racism. However, people aren't crazy-- they're showing a rational response to a crazy-making situation.