I LIVE IN A DIFFERENT country than the one into which I was born in 1942. I have never been quite able to pinpoint exactly what makes it so different. More than any other book I’ve read in recent years, Age of Fracture, by the Princeton historian Daniel T. Rodgers, has helped me to discover and to understand that difference.

One explanation for what happened holds that in the intervening years—the second half of the twentieth century—the United States shifted from the big government liberalism of the Democrats to the laissez-faire nostrums of the Republicans. There is an obvious truth to such a view, but the problem with this account, which fits so nicely into Arthur Schlesinger, Jr.’s cyclical interpretation of American experience, is that it views the changes of the past half-century as the latest replay of long-established patterns, and therefore fails to grasp just how radical some of those changes have been.

Rather than a shift from left to right, we have witnessed, according to Rodgers, a transformation from big to small. The intellectuals who shaped America’s understanding of itself fifty years ago—Schlesinger himself, and David Riesman, C. Wright Mills, and the late Daniel Bell—were, for all their faults, familiar with history, preoccupied with power, and appreciative of complexity. They also influenced political rhetoric: Eisenhower’s warning about the military-industrial complex as well as Kennedy’s 1962 Yale address  on the end of ideology seemed to come directly from their books. No wonder that the leaders who followed them were so ambitious: whether it involved deploying American military might abroad or sponsoring social reform at home, presidents as politically distinct as Johnson and Nixon were hardly shy about using the power of the state to achieve their ends.

All this changed over the course of subsequent decades, in large part because thinkers stopped thinking big. Economics is exemplary. It was not so much that Keynes lost ground to Hayek—both, after all, were European idea men shaped by the events of their tragic century. It was instead that the micro usurped the macro. The key figure in this regard is a relatively obscure University of Chicago law professor named Ronald Coase, who in 1960 urged judges not to focus on abstract questions of justice but to decide cases based upon overall economic benefit. “As economics emerged from the disciplinary crisis of the 1970s and early 1980s,” Rodgers writes, “its focus was no longer on systemwide stabilization or the interplay of aggregates. Economics was about the complex play of optimizing behavior—a thought experiment that began with individuals and the exchanges they made.” There was no longer such a thing as society, as Margaret Thatcher both informed the British and lectured the Americans, at least as far as those building economic models were concerned.

No president better illustrates the shift to small thinking than Ronald Reagan, and not just because his economic policies so strongly favored the market. Early in his presidency, Reagan seemed attracted by big ideas; his “evil empire” speech in 1983 quoted Whittaker Chambers and could have been written by Arthur Koestler. By his second term, however, darkness at noon had become sunshine 24/7. “Twilight? Twilight?,” Reagan said in 1988. “Not in America … That’s not possible … Here it’s a sunrise every day.” Cold War Reagan had become have-a-nice-day Reagan, self-actualizing Reagan, citing Tom Paine, calming the anxious, avoiding any hint of Cotton Mather-type scolding. When George W. Bush managed to link his call for a war against terror with the reassurance that no sacrifices would be necessary to fight it, he had precedent aplenty in the speeches of a president who saw “no need for overcoming, no manacles to be broken, no trial to be endured, no pause in the face of higher law.”         

Left-wing thinkers were attracted to “small is beautiful” as well. Historians focused on the conditions of everyday life, eventually leaving the stuff of high statecraft behind. What the anthropologist Clifford Geertz called “thick description” yielded fascinating insights into matters local and particular, but repudiated any hint of grand theorizing about the universal and the predictable. The influence of Foucault could be felt everywhere, and while he began his career by writing about power, by the time of his death “power had seeped out of sights and structures until it was everywhere.” Identity politics made its own contribution: by calling attention to the myriad of groups that composed society, the practitioners lost sight of the society these groups composed. Microeconomics may have reduced all action to the choices of individuals, but left-wing social theory could not even find individuals in the first place. “It is clearly not the case,” declared the rhetorician and theorist Judith Butler, “that ‘I’ preside over the positions that have constituted me, shuffling through them instrumentally, casting some aside, incorporating others, although some of my activities may take that form. The ‘I’ who would select between them is always already constituted by them.” Clearly.

One did not have to travel to the far reaches of the leftist imagination to find a rejection of the once popular notion of “We, the People” similar to the right’s retreat from national purpose. Although a preference for Burke’s “little platoons of society” found support among conservative thinkers and was expressed in George H. W. Bush’s “thousands of points of light,” liberals also came to appreciate the advantages of civil society. (Our current president was once a community organizer.) When it first appeared in 1971, John Rawls’s A Theory of Justice, thick with economic reasoning, seemed thin on liberal substance—but at least Rawls imagined society as a national community and could rightly be interpreted as a defender of the welfare state. By the time of the Carter, Clinton, and Obama presidencies, liberal Democratic presidents, quick to pick up on communitarian themes, were more likely to warn of the dangers of big government than to rely on government to promote even minimal equality. Liberalism was entering its minimalist phase. If, by society, we mean a national community tied together through obligations guaranteed by the state, there was no such thing as society on this end of the political spectrum either.

When it comes to politics, small—I am afraid to say—is ugly, and small is now everywhere around us. On the right, one former advocate of national greatness now champions Sarah Palin, while another explores brain research. On the left, Democratic activists, anxious to defend whatever is left of America’s labor movement, would react in astonishment if informed that Wright Mills, a leftist from another era entirely, denounced the labor leaders of his day as “new men of power.” Fifty years ago, John Kenneth Galbraith was a center-left economist anxious to serve the Kennedy administration; today his ideas seem hopelessly utopian, the stuff of fourth or fifth parties. It is no wonder that stalemate and polarization grip Washington these days. When there is nothing much to argue over, arguments tend to get that much more vicious.

Rodgers is not the first to explore this ground or this theme. The historian David T. Courtwright’s No Right Turn: Conservative Politics in a Liberal America is a marvelously idiosyncratic romp through similar material, and Todd Gitlin’s The Twilight of Common Dreams got there first on the question of the left’s withdrawal from a national project. But Rodgers is unsurpassed in other important matters. His ability to explain complex ideas—the Coase theorem comes to mind—is exemplary. He is unapologetic about treating intellectuals, and even academics, as producers of ideas worth taking seriously. He has the ability, unusual for historians of our day, to engage directly in current debates and to write with the clarity of a future observer of these same events. Intellectual history is never that easy to do. An intellectual history of our own time is even harder to pull off. Rodgers has done it and done it well.

Perhaps, then, this book will have the happy effect of bringing to an end the trends it brings to light. Rodgers writes about our descent into thinking small because he wants us to once again think big—or so I read between his lines. If more thinkers wrote books like this, the country in which I live may once again resemble the one in which I was born. How sweet that would be.

Alan Wolfe is writing a book about political evil.