If the left were not somewhat unhappy with Barack Obama, it would not be much of a left. That, in effect, is the underlying point of Eric Alterman’s excellent survey of the obstacles confronting a presidency the typical Nation reader could rush to celebrate. From the legacy of Bush-era incompetence and corruption to the partisan discipline of the GOP and the Roberts Court to the influence of lobbyists, one marvels that the president has accomplished anything at all. Progressive historians may well praise Obama and the Democrats for passing healthcare reform, a major stimulus and stiffer financial regulation in the face of so many structural and ideological barriers.

Still, when Senator Richard Durbin admits that the barons of banking "frankly own" the most powerful legislative body in the world, he is revealing how stark is the crisis that progressives confront. Eighteen months ago, many of us thought Obama’s tenure might rival the triumphs of FDR’s first term and of LBJ during the halcyon days of the Great Society. Now one merely hopes he will be able to blunt the GOP’s offensive long enough to win four more years in office.

But as Alterman suggests, the way to confront this reality is not to kvetch that Obama is not living up to our fondest hopes. Amid the euphoria of 2008, too many Barackophiles—of which I was one—failed to realize that no presidential campaign, whatever its rhetorical flourishes, can substitute for a social movement. Both FDR and LBJ had to respond to potent insurgencies on their left—industrial labor for Roosevelt, black freedom for Johnson. Each of these movements gestated for decades before emerging as a force that could make or unmake a presidency.

Since the feminist awakening of the 1970s, we have had several grassroots campaigns—successful ones, like the battle against apartheid; apparent busts, like the much-hyped crusade for global economic justice; and some that are still fighting for their causes (global warming, gay marriage). But there has not been a mass campaign, much less a movement, capable of addressing what should be the central domestic issue of our time: the yawning gap in income, education and healthcare between the economic elite and a majority of working Americans. Abundant analysis on this issue can be found in periodicals and websites on the left. But to translate a terrible problem into an inescapable issue requires organizations that can mobilize millions. And with private-sector unionism in perhaps terminal decline, it is not clear who will provide the organizing muscle.

While the left cannot instantly conjure up the movement we need, it can revive the tradition of speaking in credible, urgent, moral ways about the need to enact policies to aid the great majority. Alterman refers to Bush’s "ideologically obsessed presidency." What enabled these obsessives to have their way—until the Hurricane Katrina debacle—was that their ideology reigned for decades. To most Americans, the idea of slashing taxes and cutting back on regulation sounded like common sense.

Amid the frustrations of Obama’s term, those notions seem dominant once again. In July Don Blankenship, in whose West Virginia mine twenty-nine workers died this past spring, told an audience at the National Press Club, "Corporate business is what built America, in my opinion, and we need to let it thrive by, in a sense, leaving it alone." Such an obscenity—and the worldview that lies behind it—should be publicized as widely as possible.

Progressives and their sometime allies in the White House do enjoy one advantage over their opponents: unlike in the heyday of Reaganism, the American right cannot pose a single serious answer to any problem plaguing the United States or the world. Give the Great Communicator his due: communism was a tyrannical system, and liberals in the 1980s did discount the practical virtues of entrepreneurial innovation.

But a Republican Party and a conservative movement that follow the lead of Glenn Beck and Sarah Palin are dwelling in a land of perilous delusions. We need people who can broadcast that fact repeatedly and in imaginative ways—and who are rooted as much in old factory towns and fast-growing exurbs as in places like Manhattan and Berkeley. Once the left starts doing that, clever politicians will follow—at least part of the way.