Jacob Weisberg's attack on the slant of Fox News strikes me as a defense of a dying paradigm:
That Rupert Murdoch may tilt the news rightward more for commercial than ideological reasons is beside the point. What matters is the way that Fox's model has invaded the bloodstream of the American media. By showing that ideologically distorted news can drive ratings, Ailes has provoked his rivals at CNN and MSNBC to develop a variety of populist and ideological takes on the news. In this way, Fox hasn't just corrupted its own coverage. Its example has made all of cable news unpleasant and unreliable.
What's most distinctive about the American press is not its freedom but its century-old tradition of independence—that it serves the public interest rather than those of parties, persuasions, or pressure groups. Media independence is a 20th-century innovation that has never fully taken root in many other countries that do have a free press. The Australian-British-continental model of politicized media that Murdoch has applied at Fox is un-American, so much so that he has little choice but go on denying what he's doing as he does it. For Murdoch, Ailes, and company, "fair and balanced" is a necessary lie. To admit that their coverage is slanted by design would violate the American understanding of the media's role in democracy and our idea of what constitutes fair play. But it's a demonstrable deceit that no longer deserves equal time.
Is it really fair to say that Fox "made all of cable news unpleasant and unreliable"? All three are responding to market forces -- Murdoch was simply the first to recognize that a cable news channel with an ideological/partisan slant could attract larger audiences.
Also, while I have no love for Fox, which is a frequent conduit for misleading claims, it's not clear to me that non-"objective" journalism is in principle bad for American democracy or "un-American." The sad reality is that the "he said"/"she said" reporting style practiced by the establishment media legitimizes far more misinformation than Fox ever will. As my co-authors and I argue in the conclusion to All the President's Spin, responsible but non-"objective" journalism is sometimes better at countering spin than the mainstream press. With a few exceptions, Fox tends to fail to produce that sort of journalism, but there's no reason to think it couldn't be produced here in the US.
At a more general level, I see Weisberg's comments as part of a pattern in which elite pundits decry the decline of the "objective" press and/or bipartisanship, which are held up as intrinsic to American democracy. What they often don't realize or appreciate is that both were historical anomalies.
Consider objective journalism. Until the late 19th/early 20th century, the press was largely partisan. This pattern didn't change until economies of scale in printing created incentives to attract a larger audience by producing independent newspapers (see Jay Hamilton's All the News That's Fit to Sell). Similarly, the only television news available for many years came from the broadcast networks, which faced regulatory pressures and economic incentives to provide "objective" coverage as well. However, the economic incentives facing media outlets have changed and it seems likely that non-"objective" sources will again play a large role.
Along the same lines, elites have tended to privilege bipartisanship as crucial to the legislative process, but it too was an unusual feature of 20th century democracy. The troubled racial history of the South created a virtual three-party system in Congress, reducing polarization substantially:
As the South became largely Republican and the parties realigned on the issue of race, the system returned to the previous norm of polarization that we observe today.
In short, our system of government is more flexible than people realize. We're moving toward a more partisan era in Congress and the press, but that isn't necessarily bad for democracy.