I think the difference between “waspish” criticism and just being “mean shits” is easier to articulate than you suggest, Ophelia. What you’re talking about is rooted in this commonly recognized tension: Thoughtful people believe and say, for good reasons, that hostility and contempt aimed at PEOPLE is bad. However, some IDEAS are clearly deserving of hostility and contempt, and nothing but. The difficulty arises because it’s difficult, perhaps even impossible, to keep the hostility and contempt for the bad ideas entirely separate from the people, because it’s the people who embrace the contemptible ideas.
But which comes first, and why, does matter. Criticizing people for having bad ideas is perfectly reasonable and respects their fundamental humanity; in effect, such criticism asks others to be better people by chiding them for ideas which are bad but *which they can change*. Recognizing someone’s humanity means, ultimately, recognizing their autonomy and consequently their responsibility: You have this belief, advocate this position, and take these actions — and I argue that they are horrible beliefs and positions and actions, and that such beliefs and behaviors make you a bad person. My criticism respects your humanity by holding you accountable for your choices, and is consistent with encouraging you to make better choices and thereby become a better person.
Criticizing people for who they are — attacking their character and identity rather than their beliefs and actions, especially when the attack is on a part of their identity that is not chosen or subject to change (gender identity, able-bodiedness, race, etc.) — does not show the same respect for humanity. Generally speaking, such criticism places ideas in a secondary role: Instead of saying that you are bad because and only to the extent that you have bad ideas and engage in bad behavior, such criticism declares that only a person who is fundamentally bad would embrace such a bad idea or behave in such a way. Such criticism bears no element of encouraging or recognizing the possibility of change in it, and shows no respect for the humanity of the one criticized.
Thus, what separates a sharp and witty critic like Jon Stewart from some asshole who thinks he’s witty but is actually just a mean shit — Rush Limbaugh is a paradigm case — is the recognition of a fellow human’s humanity even when one thinks that fellow human is being a complete shit and has horrible beliefs that motivate horrible behavior. For example, Stewart will criticize Faux News broadcasters by eviscerating their bad ideas and actions — their hypocrisy, self-contradiction, blatant denial of reality, systematic deceit of the public, lack of journalistic integrity, and so on. But his criticism consistently puts the priority on the ideas: you are bad people because you have and promote bad ideas, and by implication you would be better people if you had and promoted better ideas. For the perfect counter example, Rush Limbaugh’s criticism of Sandra Fluke for testifying about the mandate for insurance to fund birth control under the Affordable Care Act was to label her a slut and generally belittle her with every misogynist insult he could spit into his microphone: He offered no real criticism of the ideas Fluke advocated, and he dismissed the idea of birth control subsidies as so obviously wrong-headed that they are something only a bad person would ever argue for in the first place — a filthy slut like Fluke.
Now, those are extreme opposite ends of a spectrum for illustrative purposes, but I think the underlying distinction is basically right: We can and should criticize people for bad ideas and bad behavior, and that can and should be uncompromising and even cutting when necessary, but such criticism is ultimately respectful of the humanity of others because it implies that they can become better people through embracing better ideas and behaviors. But attacking people for their identity rather than their ideas — especially for elements of their identity that they cannot change or choose — or suggesting in any way that their ideas spring from or should be judged according to their identity rather than the other way around, is fundamentally dehumanizing because it denies the very possibility of choice and improvement.