They went after Obama for the same reason that people told jokes about Al Gore inventing the Internet. To entertain and to sell their product.

Like I said they have a constitutional right to do it. but we don't need to be suckers and pretend they are on out side.

The idea of a "liberal media" is a creation of propagandists on the right to cause us to distrust sources of news and opinion and to give equal weight to their propaganda in the name of "balance".