The refrain is familiar and bizarre at the same time. Leftists bash Tea Partiers as racist, violent, revolutionary, and dangerous. How could they come to such conclusions about a group that, even when it gathers by the tens of thousands barely even litters and also shows a strong affection for an actual American black, Hermann Cain?
Simple. The Left remembers their own period of protest, which was much different than now.
Left wing protests in the 1960s made a habit of race-baiting and used shockingly vile language against whites.
Left wing protests sparked actual violence in most major cities. It seems that they could not congregate at all without causing a riot.
The Left called for violent overthrow of the system and used the language of power, control, and even murder.
This is the Left's historical memory of protest. It is not surprising that they would assume that the Tea Party would behave as badly as them. It frustrates them that conservatives have not destroyed their own movement in the same fashion as the Left.