But now that the old behemoths of the news are in decline, the unified public they assembled is fading too. Neither the broadcast networks nor the newspapers have the reach they once did, raising concerns about whether the press will be able to serve its classic function as a watchdog over government. That problem also has a flip side. Precisely because the press is often critical of political leaders, it provides them legitimacy when it validates the grounds for their decisions. A press that is widely trusted by the public for its independence and integrity is also a resource for building consensus. Thus when the public sorts itself according to hostile, ideologically separate media—when the world of Walter Cronkite gives way to the world of Glenn Beck and Keith Olbermann—political leadership loses a consensus-building partner. This is the problem that faces Barack Obama. It is not, however, an unprecedented one.

To most Americans, at least until recently, it had long seemed a settled matter that the media should have no relationship with political parties—but that has not been the norm throughout American history, much less in other countries. In many democracies, newspapers and other media have developed in parallel with political parties (sometimes directly financed and controlled by them), while elsewhere the media have been independent, with no partisan connection. The prevailing model for how American presidents interact with the media has gone through three historical stages. As a young republic (and to a large extent even after the Civil War), the nation had partisan newspapers; the second stage, stretching across the 20th century, was characterized by powerful, independent media outlets that kept their distance from the parties; and in the third stage, we now have a hybrid system that combines elements of the first two.

The founding period in American history created a new and richly supportive environment for the press. Britain and other European states, seeing popular newspapers as a political threat, had limited what they could say and imposed heavy taxes to raise their costs and reduce their circulation. America’s Founders, in contrast, believed that the circulation of news and political debate could help preserve their fragile republic. So besides guaranteeing the press its freedom, they excluded it from taxation and subsidized its development by setting cheap postal rates for mailing newspapers to subscribers. The government thereby underwrote the costs of a national news network without regulating its content. Public officials also subsidized specific newspapers they favored, by awarding generous contracts for government printing and paying fees for official notices. Together with subscription and advertising income, the postal and printing subsidies provided the financial basis for a development of the press so rapid that by 1835, the United States, even though it was still almost entirely rural, probably had the highest per capita newspaper circulation in the world.