Like a lot of Americans, when I woke up Friday and found out there was manhunt in the Boston area for the remaining suspect in Monday's bombing at the marathon, I turned on CNN.

It's a common impulse, although less common than it used to be. The news audience has been chopped up into ideological camps, and CNN's middle way has been clobbered in the ratings. The legacy networks like NBC can still flex powerful muscles, and Twitter and other real-time social media sites have seduced a whole new cohort of news consumers.

But the biggest damage to CNN has been self-inflicted - never more so than in June, when in a rush to be first, it came running out of the Supreme Court saying that President Barack Obama's health care law had been overturned. It was a hugely embarrassing error.

Still, when big news breaks, we instinctively look to CNN. We want CNN to be good, to be worthy of its moment. That impulse took a beating this week. On Wednesday at 1:45 p.m., the correspondent John King reported that a suspect had been arrested. It was a big scoop that turned out to be false.

King, a good reporter in possession of a bad set of facts, was joined by The Associated Press, Fox News, The Boston Globe and others, but the stumble could not have come at a worse time for CNN. When viewers arrived in droves - the audience tripled to 1.05 million, from 365,000 the week before, according to Nielsen ratings supplied by Horizon Media - CNN failed in its core mission.

It was not the worst mistake of the week - The New York Post all but fingered two innocent men in a front-page picture - but it was a signature error for a live news channel.

CNN has been in the middle of a rehabilitation ever since Jeff Zucker was appointed at the end of last year to run CNN Worldwide. Until now, the defining story in the Zucker era had been a doomed cruise ship that lost power and was towed to port, where its beleaguered passengers dispersed. This week, CNN seemed a lot like that ship.

It's clear after a busy week that Zucker can hire all the talent he wants, broaden the scope of their coverage and freshen the look of the joint, but if the network continues to whiff on the big stories, all of that will be for naught. Two people I spoke to at the network, which featured a lot of good work and tireless reporting when it wasn't getting it wrong, called the error "devastating."

Twitter and commentators vibrated with umbrage - "Breaking News Is Broken" suggested a headline on Slate - all asking some version of how can this keep happening.

Here's how: As a general practice, wall-to-wall live television reporting is perilous. Maybe instead of the constant images of police tape, television news should frame their own coverage with a virtual version, indicating that viewers proceed at their own risk.

Despite suggestions otherwise, people who are on the air talking about the news cannot report while they are doing it. Producers make hundreds of decisions on the fly. The incrementalism and vamping required to fill the hours - "Again, as we have been saying, Anderson ..." - makes everyone desperate to say anything vaguely new.

Throughout the week, I saw anchors and reporters staring at their phones, hoping a new nugget might arrive to give them something to say. (Memo to television executives everywhere: News is a better product when presenters look at the camera.) And the live environment means that at a certain point, the bosses have to quit shouting into the ear piece, trusting their staff and crossing their fingers.

Several people involved in reporting the Boston bombing case said the story presented particular challenges. In a large-scale assault on public safety, the audience wants to know everything, right this second. Yes, they want you to be accurate, but the implicit promise of a 24-hour news service is that it will happen quickly.

The pressure to produce is ratcheted up accordingly. Editors and producers begin leaning on their reporters, and they, in turn, end up in the business of wish fulfillment, working hard to satisfy their audience, and meeting the expectations of their bosses. It creates a system in which bad reporting can thrive and dominoes can quickly fall the wrong way.

Most important, the scope of the crime, the number of victims and the fact that it smacked of terror on American shores provoked a vast law enforcement response at the federal and local level. A multiagency array of command centers and responsibilities created a target-rich environment for reporters. But it also created an patchwork of sources, all operating in the fog of war, albeit a domestic one.

By Wednesday, the Federal Bureau of Investigation began to hold information much more closely. That left other local and federal agencies less in the know. It wasn't long before those who did know weren't talking, and those who talked did not know.

King, a native of the Dorchester neighborhood of Boston, was deeply sourced with local law enforcement officials, but people covering the story suggested those sources were out of the loop by Wednesday.

"It was never a local case to begin with, and then it was decided to button it up to prevent further leaks," a former law enforcement official told me.

Up until then, King had been having a very good run in Boston. After losing his anchor spot on CNN, he was in the middle of demonstrating value on the reporting side and was straining to own the story. But even good reporters with good sources can end up with stories that go bad, and keep in mind that The Associated Press - a stalwart in breaking news and King's former employer - was reporting the same thing. Its reporting gave him someone to hold hands with on a breaking development.

In a statement, CNN said that it had "three credible sources on both local and federal levels. Based on this information we reported our findings. As soon as our sources came to us with new information, we adjusted our reporting." (At least King dialed back his story in plain sight. The AP oddly continued to stand by its report with a mealy-mouthed statement.)

So what is the real damage of a stumble in a very complicated story? People at CNN said that they got significant blowback from sources, but Zucker seemed fine with the overall effort, issuing a hero-gram to staff Friday, before the final chapter unfolded.

"All of you, across every division of CNN Worldwide, have done exceptional work," the memo read. "And when we made a mistake, we moved quickly to acknowledge it and correct it."

That's one way to spin it. I talked to several competitors who did not commit the same error, and one spoke for many when he said: "It was bad enough - really, really bad - so that they made all of us look terrible. Nobody comes away a winner from something like this."

If legacy media were falling short, the new order did not look all that promising either. A crowd-sourced witch hunt took place on Reddit, identifying innocents as suspects, and Twitter was alive with both misinformation and outrage at the mistakes. (There were many curiously triumphal posts about the death of old media in Twitter feeds that were full of links to that same old media.)

Part of the reason that we still want CNN to be great is that at a moment when information and news seem to have done a jailbreak - bursting forth everywhere in all sorts of ways - it would be nice to have a village common where a reliable provider of news held the megaphone. By marketing itself as the most trusted name in news, CNN is and should be held to a higher standard.

After the erroneous report of a capture, CNN's reporters and anchors seemed to have taken a deep breath and proceeded with caution. On Friday, the network got an early jump on the story, but stayed on cat's paws throughout the day, issuing regular caveats on every bit of information. In the end, NBC broke the news first.

When the news finally broke with certainty - in a sign of the times, the Boston Police Department confirmed it on Twitter before many outlets, including CNN, did - chants of "U.S.A.! U.S.A.! U.S.A.!" could be heard on the streets. But even as Obama took to the air to cite the police work that made that moment possible, he talked about the reporting that fell short.

"In this age of instant reporting and tweets and blogs, there's a temptation to latch on to any bit of information, sometimes to jump to conclusions," he said, his face turning sour as he spoke. "But when a tragedy like this happens, with public safety at risk and the stakes so high, it's important that we do this right. That's why we have investigations. That's why we relentlessly gather the facts."

Like everyone else, the president wants to have a press that is equal to the people it serves. He wants CNN to be good.