Clive Crook pushes back:
The problem with anger is that it makes it harder to think clearly. It's just bad practice. ... Even if the result is not physical violence, it is exaggerated political turbulence and discontent. Shafer seems to want as much of these as we can get, without actually coming to blows. Those African countries riven by tribe? They're so spirited! Basically, aim for civil war, then pull it back just a notch.
That last sentence seems to me to be a pretty good definition of Rovian calculation to me.