If the news media is so biased, why did they turn on Obama?

Pres. Obama's performance in the debate last Wednesday received uniformly negative reviews.  In response, some liberals ask, reasonably, how come, if the news media is as biased as non-liberals say, they turned on Obama?  There are three factors at work:

First, while the news media routinely lie, they can't lie easily about a debate if you just saw it, unedited, on live TV.  Further, they knew from the focus groups and instant polls that it was obvious to viewers that Obama failed.  This limits the journalists' options.

Secondly, and, I think, more importantly in this case, liberal journalists and commentators were  themselves shocked by Obama's poor performance.  They had believed their own spin.  They had demonized Clint Eastwood for his empty chair comedy routine.  Now, they saw, along with the rest of the country, that Eastwood was right.  They were in shock.  Anti-Obama rants, like the one from Chris Matthews, were the result.

Thirdly, a key feature of liberal news bias is that the journalists are loyal first and foremost to the liberal world view.  Journalists will abandon a politician the moment that he does not serve the cause.  You may remember that happening to John Kerry.  They are loyal to the message, not the messenger.  If it starts to look like Obama is making liberalism look bad, they will abandon him too.  Most of the media has not gotten to this point with Obama but the new New Yorker cover (above) indicates that this may change.