More from Atrios:

While the op-ed pages and gab shows have occasional contributions from "experts," or at least people claiming to be experts (think Norah Vincent being a Senior Fellow at the Foundation for the Defense of Democracies, terrorism think tank), primarily, the public pontificators are simply pundits who don't know much about anything but who feel free to present their uninformed opinions on everything under the sun.

I can recall a few years back reading an article by a guy who was called to be on O'Reilly to discuss something he had some particular expertise in. While the guy was waiting to go on the show there was some breaking news story and FOX didn't have anyone ready to go on and talk about it. So the producers quickly hustled this guy out to respond to questions from Bill on a matter completely apart from what he was originally there to discuss. Bill kept peppering him with questions on this story and he told Bill repeatedly that he didn't know enough to give an opinion on the matter. He was never invited back again. This is how the media world works: the selection process for pundits encourages them to talk about things they know nothing about. If they were to answer honestly and say, "I don't know," they wouldn't get invited back. If they don't get invited back then they can't build their name recognition. If they can't build their name recognition then they can't get the higher fees that come with that recognition. If they don't become a well-known pundit then they can't make the six figure book deals and hang out at the right parties with important people who will hang on their words as if they actually mean anything. The pundit world is full of people who are expert at being experts.