This idea explains a lot of what you see happening on the City-Data.com chat boards about American politics.
He mentions a sociological study in which Rs and Ds were most eager to read arguments from those who reflected their own points of view.
http://www.nytimes.com/2009/03/19/op...19kristof.html
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Almost half of Americans now live in counties that vote in landslides either for Democrats or for Republicans, he said. In the 1960s and 1970s, in similarly competitive national elections, only about one-third lived in landslide counties.
“The nation grows more politically segregated — and the benefit that ought to come with having a variety of opinions is lost to the righteousness that is the special entitlement of homogeneous groups,” Mr. Bishop writes.
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The danger is that this self-selected “news” acts as a narcotic, lulling us into a self-confident stupor through which we will perceive in blacks and whites a world that typically unfolds in grays.
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PLEASE READ THE COLUMN. I'M ONLY VERY INCOMPLETELY DESCRIBING ITS CONTENTS.