See Cass R. Sunstein - Why Societies Need Dissent<ref>[http://papers.ssrn.com/sol3/papers.cfm?abstract_id=441340 Sunstein, Cass R., Why Societies Need Dissent. Harvard University Press, September 2003]</ref>, and slso also this article that suggest suggests that social networks will create an increase in group polarization<ref>[http://arxiv.org/pdf/physics/0603023.pdf Petter Holme and M. E. J. Newman, Nonequilibrium phase transition in the coevolution of networks and opinions, Physical Review E, 2006]</ref> '''affective polarization''': meaning that our feelings (affect) are different towards members of our own group compared to outsiders. Growing intolerance in the U.S. is a puzzle because disagreeing about policies need not cause rampant mistrust and legislative gridlock