Our civic faith in getting and spending

America is a place of unprecedented affluence, and its focus on worldly goods has manifested itself in many ways - from its culture of acquisitiveness to the undernourishment of its public sphere. In fact, the act of consumption is an integral part of American personal and collective identity. Harvard historian Lizabeth Cohen has taken the nation's postwar history and rewritten it from this perspective - the rise and ongoing evolution of what she terms "A Consumers' Republic."

Cohen has a central and worthwhile observation - that the ideology of consumption has evolved dramatically in the space of an American lifespan, and can be broken down into three phases.

In the first, originating in the Great Depression, consumption was an integral aspect of life's political experience. The class and political consciousness that permeated a nation one-quarter ill-housed and ill-fed extended to purchasing collectives, mass-based consumer organizations, and the idea that the consuming class and the producing class had little in common.

The burgeoning affluence of the postwar period changed that. As Cohen demonstrates, consumption became a tacit patriotic act. Government subsidies for highways and residential housing gave Americans suburbs and enabled the consumption patterns that accompanied them. Industrial planners built their plans around this ever-expanding and ever-willing consumer base. Cohen pays less attention to the manipulation of consumer wants, however, than to the unifying role consumption played in American identity - by shopping together, we're all in this together, so to speak. But as she points out, this was more an ideology than a reality - the fruits of American prosperity were far from equally shared.

By the mid-1970s, the idea of an egalitarian society enjoying a shared trip to the store became a hollow one. The nation was mired in "stagflation," and experienced a dramatic downshift in the growth of productivity and real wages that was to last for more than two decades. The resulting disaffection led to a revival of a mass consumer movement. By the mid-70s, America was perilously close to having a cabinet-level department of consumer affairs.

But, as Cohen describes, the science of marketing responded by moving away from mass consumption and toward "segmentation" - using demographic data and survey research to break the population down into subgroups with common lifestyle and buying habits, from affluent soccer moms to pickup-driving good ol' boys. Today, marketing is a matter of targeting these segments, reaching them, and planning how to move on to adjacent segments.

To Cohen, this segmentation resonates with other trends that have eroded our nation's communality, such as privatization of basic services and the rise of gated communities. Thus, in the space of a lifetime, consumption in America has gone from a militant "We want ours" to a jaded "I've got mine."

There are a number of lenses through which the American journey may be viewed - class conflict, income distribution, race or gender relations, urban versus rural life, and so on. Black and white America, for example, are not unequal because they have different consumption patterns - rather, their consumption patterns are different because they are unequal in a more fundamental and insidious sense. But, as Cohen shows, consumption has been one of the realms in which all of these struggles have been played out. Indeed, her Consumers' Republic has always been host to the conflict between business and government leaders who saw consumption as a homogenizing social force and disaffected groups who saw it as a way to their betterment.

Cohen's retelling of the historical record takes us to the precipice of other important questions. The first is America's agonizingly low savings rate. And a second, and deeper, question is: Are we really better off?

Robert Kennedy once remarked: "Gross National Product counts ... special locks for our doors and the jails for people who break them. [But] it ... measures neither our wit nor our courage, neither our wisdom nor our learning, neither our compassion nor our devotion to our country.... And it can tell us everything about America except why we are proud that we are Americans."

Poverty and want around us still leave material goods profoundly relevant. But as we look at a future of sprawl, social fragmentation, global climate change, and other collective ills, the next phase of the Consumers' Republic may be conflict over the way we define its success.

• Everett Ehrlich is senior vice-president and director of research at the Committee for Economic Development, a public policy think tank in Washington.