But beyond humor that misses, with some audiences or with all, what characterizes snark? Two things, I think. One is that it is an appeal to emotion – it is a statement with a particular affect, and the affect is an appeal to an attitude in which both writer and reader participate, but they participate in an exclusionary way. This is what makes it a branch of irony. Instead of arguing to everyone on the basis of shared reason so that, at least in principle, everyone could be included in the shared sentiment, snark depends upon exclusion. It is a refusal to offer a public argument, with the possibility of reasoned inclusion, and instead depends upon prior shared views that merely exclude because snark does not make an attempt to persuade. It is ‘affectively exclusionary’ in the language of moral psychology.
Two, because snark depends upon a prior shared commitment, it is a form of question-begging argument. Not precisely a form of argument, because it is about affect, not reason. So, more precisely, snark is the affective cognate of a question-begging argument, in which the sentiment of the conclusion assumes the sentiment of the premise. It assumes that one already shares the attitudes necessary to … share the attitudes.