I think consistently referring to counter-protestors as "zionists" is probably misleading; I suspect that while there may be many genuine zionists doing violence to pro-Palestine protestors, there are also probably a bunch of fascists mixed in there who are very much not "zionists" in the traditional sense (other than perhaps that Israel's continued existence provides a potential avenue to ethnically cleanse the US of Jews).
Using that broad brush actually plays into the fascists' agenda.
