This presidential election has already produced its fair share of predictable foolishness and sheer demagoguery. The candidates have promised to heal the sick, fix the economy, and create wealth without risk, even if they don't quite understand economics.
Amid all this noise, suddenly we hear a signal coming from new book The Big Sort by journalist Bill Bishop. While John McCain and Barack Obama promise to lead the nation costlessly toward nirvana, Bishop informs our understanding of the past and suggests a future that belies the hopes of both candidates for the White House.
Bishop argues that over the past 40 years Americans have increasingly chosen to live near others who are culturally and politically similar. When Jimmy Carter beat Gerald Ford, less than one-fourth of Americans lived in counties where the presidential election was a landslide. By the time George W. Bush won re-election, almost one-half lived in landslide counties.
Bishop writes well. The book is an engaging read, filled with stories about how the United States has changed over the past 30 years. But Bishop is more than a storyteller.
He worked with Robert Cushing, a sociologist from the University of Texas at Austin -- to document the internal migrations that have made the nation both more separate and more homogenous.
There is a larger story here. Americans are become wealthier and more economically secure. That security has brought what my colleague Brink Lindsey calls, in the title of his latest book, The Age of Affluence, a period when material concerns no longer dominate politics and life.
In the place of such concerns, Bishop says, people reorder "their lives around their values, their tastes, and their beliefs." Neighborhoods, churches, and civic organizations became more homogenous as have the political parties.
The Big Sort traces these cultural divisions to the conflicts of the 1960s and afterward. Religion is an important part of Bishop's story. He traces the decline of mainline Protestantism and shows how evangelicals succeeded in attracting new members by emphasizing what people had in common. Bishop is a liberal -- he says as much from the first page of the book -- but his treatment of Christianity, and not least of conservative Christians, is fair enough.
Bishop also has some blind spots. He emphasizes the collective consequences of migration decisions by Americans. The subtitle of the book passes a harsh judgment on those choices: "Why the Clustering of Like-minded American Is Tearing Us Apart."
But these decisions about where to live are choices made by adults, choices that are fundamental to their conception of what makes for a good life. The United States promises the pursuit of happiness, not the pursuit of happiness unless it makes us too polarized.
The book also worries too much about the political consequences of the Big Sort. Americans are coming to live in small tribes, Bishop argues, where cultural and political differences are not encouraged.
Living with the like-minded is perhaps a matter of some regret. But living with the enemy also has its problems. Who is to say that moving to a place bounded by a horizon does not make more sense for a family and the nation? The alternative might be greater conflict locally.
The Big Sort has some vital lessons for the presidential candidates. McCain speaks of "our nation" as if we were a family while Obama says there is only a United States rather than red and blue states. On the evidence in this book, both candidates are wrong.
The nation is deeply divided culturally and politically. The geographical separation reflects the cultural divisions that have informed politics for many years. People do not enjoy living near people who despise their deepest commitments. They move away from them. The nation becomes less united.
That change has advantages and disadvantages. The advantages? Greater division means the nation lacks the unity necessary to go on great collective crusades. We simply don't agree about the goals for such a crusade.
A genuine enemy might enable McCain to unite a disparate nation, but few now believe radical Muslims represent a mortal danger. Once Obama stops talking about "a common purpose" and starts governing, he will discover concretely how little Americans have in common.
The nation does need a leader that understands and accepts that Americans need some geographical, political, and cultural distance from one another. America needs, in other words, a president who knows We do not exist.