The premise of "Searching for Whitopia: An Improbable Journey to the Heart of White America," Rich Benjamin's examination of white flight from the suburbs to the exurbs, seems slightly archaic: Just 10 months ago, black and white voters swept the nation's first black president into office, a step hailed worldwide as the dawning of "post-racial America."

But after a long, hot summer of racially tinged discontent -- think "birthers," President Obama's "beer summit" with a white cop and a black professor, and Rep. Joe "You Lie!" Wilson's angry outburst -- Benjamin's journey to the largely hidden heart of whiteness seems prescient. The book, chronicling a hip young African-American's time living in affluent, overwhelmingly white communities he calls "Whitopia," illuminates the anti-Obama, take-back-my-country ire of recent months.

From 2007 to 2009, Benjamin left his cosmopolitan digs in Manhattan and moved into enclaves such as Carnegie Hill in New York City; Forsyth, Ga.; and Coeur d'Alene, Idaho, former home of the 1990s white supremacist movement. Benjamin, a Stanford-educated academic who grew up in a well-heeled Washington, D.C., suburb, befriended the locals, attended government meetings, hosted dinners and generally tried to figure out what makes the "Whitopians" tick.

His findings -- that upper-middle class whites are searching for a mythical, Mayberry-esque place of tranquility and homogeneity -- aren't shocking; neither is the Whitopians' rejection of being labeled racist just because they have chosen to live in communities that are more than 90 percent white. They tell Benjamin they simply want what all of us do: a life free of crime, high taxes, loud rap music and Spanglish.

Benjamin, however, points out that U.S. Census Bureau projections show that young Latinos will become the nation's majority population by 2024, a demographic shift that will dramatically shrink exurban whites' ballot-box power and calcify red-state, blue-state polarization. Exhibit A: the 2008 presidential election, in which John McCain took nearly all the mostly white, exurban South, but Obama claimed the White House with votes from multiethnic cities and first-ring suburbs.

Although most Whitopeans literally embraced Benjamin -- he lunches with western Republicans, plays country-club golf in Georgia and attends an Idaho white-power church retreat without even a hint of hostility -- he points out that their collective arguments for self-segregation are as bigoted and insidious as a Klan rally. Their attitudes, cloaked in race-neutral code words like "clean," "safe" and "comfortable," Benjamin writes, fuel racial paranoia, hamstring upwardly mobile blacks and foment an antidiversity backlash among working-class whites who long for access to "the good life."

"Whitopia" also reveals self-delusion and simmering anxiety in the exurbs. Its denizens reject high taxes even as they strain government services; they work harder and commute farther to maintain their lifestyles; and they helped hasten the demise of Republican moderation, sending a parade of combative arch-conservative Republicans to Congress (Wilson represents exurban South Carolina, and Michele Bachmann's district includes well-off Minneapolis suburbs).

Benjamin's jumpy style takes some acclimation, and the tales he tells aren't always in a linear, straight-ahead narrative. But when tens of thousands of Tea Party protesters arrive in Washington to vent wide-ranging anger at illegal immigration, taxes, bailouts, "socialized medicine" and Obama's very presence -- depicting him as both a neo-Hitler and an African witch doctor -- the book seems right on time.

Joseph Williams, a former assistant managing editor at the Star Tribune, is an editor at the Boston Globe.