I guess it's not really new, but it's used in a new context. Accuse people who point out Tea Party craziness of being "name callers". What's worse than advocating domestic terrorism? Pointing out that someone advocates domestic terrorism.
The idea is that the craziness of the Tea Partiers does not detract from their ideas. I reckon that would be true if the movement actually had any ideas and was anything other than a manifestation of a generalized reactionary discontent. In principle, the movement has certain not very controversial objectives such as smaller government and lower taxes, but it appears that the rank and file are willing to use violence to air their vaguely expressed grievances and, if not willing to use it or advocate it, to condone it. This makes it very hard to trust them on any issue or to take their positions seriously.