Nearly everything I thought I knew about American politics was wrong.
A few years ago, I read The Creative Class, by Richard Florida, which documents how artists, programmers, writers, and others who create wealth are clustering in specific cities and fleeing others. Florida's excellent book also documents how this population shift results in greater wealth for cities favored by the creative class, and economic fail for the cities they abandon; and how this creative class typically favors liberal politics.
So I should have seen this coming, but I didn't. If specific cities are typically better educated, with a higher average income, and more liberal, there must be other cities which are typically less well-educated, with a lower average income, and less liberal.
The Big Sort, by Bill Bishop, shows how Republicans and Democrats have been separating geographically since the 1970s, and further traces this phenomenon to the growing polarization of American politics. (In 2006, the Senate broke its previous record for polarization, which was set two years after the end of the Civil War.) Bishop provides ample evidence that these two trends are closely related, and very probably causally related, both through historical analysis of the voting record, and by delving into psychological and sociological research about the polarizing effects of like-minded groups.
One reason Democrats and Republicans so rarely agree on anything any more is that the social dynamics of like-minded groups dramatically encourage polarization; but another is that the two parties increasingly represent entirely distinct nations. When Sarah Palin referred to rural America as "real America," she echoed and confirmed a growing Republican identification with, and habitation of, exurban areas. In Red America, most people live outside of the city, education is less important, incomes are lower on average, nobody doubts the justice of the invasion of Iraq, and Bush had a terrific approval rating. In Blue America, it's the reverse.
Yes We Did, by Rahaf Harfoush, tells the story of the Obama campaign, but leaves out some very important historical context, which The Big Sort provides. Although the technologies and systems of the Obama campaign came straight from social software, with a founder of Facebook leading the effort, the strategies and tactics came straight from the 2004 Bush campaign, which had in turn adopted them from tactics which Evangelical Christianity developed in India and Asia, and later re-used with phenomenal success in the United States.
The tactics rely on gathering groups of like-minded people to encourage one another to vote. Despite Obama's bipartisan rhetoric, he ran (and won) an entirely partisan campaign. It's unlikely he would have won any other way; The Big Sort contains countless stories of moderates losing seats to partisans in recent years, as, indeed, do the headlines. Moderates not only lose seats, they are disappearing entirely as a political constituency. The Big Sort gives you the statistics, so I'll just give you the short version: both the absolute number of moderates, and the percentage of moderates in any particular election, have been shrinking rapidly since the 1970s.
As Public Enemy would say, the future holds nothing else but confrontation.
At the Federal level, this doesn't say good things for our democracy. If like-minded group effects continue making politics more and more partisan, elections could get more and more vituperative, laws more and more controversial, until the common ground disintegrates entirely. However, at the local level, the transformation from heterogenous to homogenous communities means that political unity is very easy to achieve, and consequently you have liberal states decriminalizing marijuana while conservative ones pass laws like the Texas School Children's Religious Liberty Act.
The same forces that debilitate government at the Federal level make it dynamic and innovative at the local level; whether this is a good thing or a bad thing remains to be seen. Although the ability to create local spaces which reflect how people want to live sounds terrific, the larger-scale repercussions are unnerving, to say the least, for a nation with a potent, sizeable military and intense involvement in foreign affairs all over the planet. If you're a smaller country watching a big country with a lot of nuclear bombs alternate wildly between polar extremes, it could make you nervous. The Big Sort also cites research which shows a similarly divided situation in Germany immediately preceding the rise of the Nazis. (Probably fearing Godwin's Law, the book only mentions the research in a footnote.)
The Big Sort made me rethink everything about politics. I'm not done rethinking and it'll probably take me quite some time. I can't recommend this book strongly enough. I'd even go so far as to say that forming political opinions without reading it is reckless.