In the end, it’s usually our principles that betray us. Former CNN chief Rick Kaplan told Ken Auletta in his 2004 biography of founder Ted Turner, “Basically, the Fox prime-time schedule is just talk radio. And with the networks convinced they don’t need to cover the world, there really is a need for CNN. You need to have one network that really covers the news, not talks about covering the news.” As it turns out, of course, he was wrong: Last week, Nielsen reported that CNN had lost roughly half its prime-time viewers in the first quarter of 2010 compared with a year earlier, despite news events like the Haiti earthquake. Meanwhile, Fox News’s “talk radio” on TV propelled it to second place among all cable networks in the same time period. In 2009, led by the twin riders of the apocalypse Glenn Beck (up 50 percent year over year) and his comparatively more fact-based coeval Bill O’Reilly (up a mere 28 percent, but still boasting an audience nearly five times that of Larry King’s), Fox had its best year ever.

It’s easy to forget that CNN was once revolutionary. Founded in 1980, back when the idea of watching a channel other than ABC, NBC, or CBS seemed exotic (Fox would not start for another six years; Fox News not till 1996), it was, in terms of cultural impact, the Google of its day. Its gonzo “fluid news” style, low-cost methods, and disdain for the woolly orthodoxies of traditional TV news- gathering terrified the big three, and attracted their most forward-thinking journos. And the internal contradictions in Turner’s vision (public service versus profit growth) were for years obfuscated by the extraordinary cash-spewing awesomeness of the cable business. By 2000, CNN was making $300 million, causing Jerry Levin, the CEO of Time Warner, to rank CNN alongside Time magazine as the “crown jewels” of his empire.

It’s hard to see the fervor of early CNN in today’s product, with chummy King cozying up to out-of-date celebrities and the resolutely humorless Wolf Blitzer stumbling through banter with Jack Cafferty. As with USA Today, CNN’s best work and workers (Sanjay Gupta, Christiane Amanpour, Fareed Zakaria) strain to break through a stultifying smog of midmarket general-interestness, neither high-toned enough to feed into upmarket affectations nor downmarket enough to be … fun.

The news of CNN’s decline prompted a flurry of free advice, from bringing back Crossfire to NYU media prof Jay Rosen’s idea of having a show produced by liberals about conservatives, and vice versa. But it’s always easy to pontificate when you’re not weighed down by decades of process, staff, relationships, and cash flow. Would you want to tell Larry King it’s time to retire?

But CNN’s biggest problem may actually be its founding principles. In an era when news flows like water—available everywhere, all the time, instantly—a network devoted to providing headlines topped with a touch of analysis no longer seems quite so useful. If anything, sitting down for 22 minutes to watch a middlebrow mix of politics and weather that’s too proud to dabble more than passingly in the latest Hollywood crack-whoredom seems … inefficient. What was very urgent in 1980 or on 9/11 no longer seems crucial when we’re drowning in news. CNN’s decline may be, in Wall Street analyst-speak, secular as opposed to cyclical.

As bulwarks of old media are discovering, it’s hard-to-nigh-on-impossible to refresh an entrenched brand at the speed required by our rapidly metastasizing digital culture (and wait till we’re all watching video on our iPads!). CNN took two generations to go from vanguard to rearguard. It should consider itself lucky. AOL and Yahoo, both now in the throes of their own frantic rethinks, only got one.

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