Why Democrats don't fight back
The Dems don't fight back against the fake right-wing outrage because it serves their purposes. They don't care that the right-wing are liars and they don't even mind most of the lies. They don't like being personally targeted by the right (because their friends can be bloody dangerous), but the lies actually serve their purposes. You never hear them complain, for example, that right-wingers consistently lie about what the President's job is, because they don't particularly want anyone to do the President's actual job. In fact, an overwhelming amount of the current public debate is about pretending that the President's real job does not exist - his real job, it is now averred, is to be "the Commander-in-Chief", and the discussion is about how he can do that job much better if he can just, y'know, ignore that Constitution thing. It must be true, because even Obama seems to agree, and I remember hearing all about how he is a Constitutional scholar throughout the campaign.