I agree fully with Hilzoy Michael Savage is angry nearly all of the time (and time after time it is clear he lets the anger control him). Ann Coulter is not constantly angry but I can see why someone would characterize Ann that way. But Rush? Quite obviously Hilzoy is working off of the old angry white guys as conservative voter theme from the 90s. Perhaps he is mistaking the anger he feels towards Rush when he listens to Rush as Rush's anger.
Now more general commentary about anger. Anger is one of our emotions and it is important. Few emotions motivate as much as righteous anger. The trick is to control the anger by channeling it into proper outlets. I see a lot more on the left improperly channeling that anger, in fact, it appears the anger controls them and not the other way around.
I wonder what the records indicate. While I am not claiming the right is free of angry nutters I don't recall hearing about calls for violence against the President Clinton in the amount I hear them with respect to President Bush. It is nothing to find them or hear them, in fact during the GOP convention in NYC there were plays being actively advertised that acted that scenario out. I went to a blog based in the UAE and the writer essentially was pining for an assassination.
I bet the signs at a protest run by conservatives and those by leftists are radically different too. I bet the number of words one tries to keep their children from learning are much more predominant on leftist signs than conservative signs.