Sykes’ defenders found her pungency unexceptional, and it is. It represents a whole genre of political discourse: the rhetoric of the rant. This approach recently introduced the “c” word into the national debate on gay marriage. It leads some spotlight-chasing conservatives to attack opponents as “traitors” and to employ racist epithets. It is the dominant form of public comment on the Internet, where the pithy, personal, scatological attack has become a minor art form, rather like sculpting in excrement…

The answer, of course, is the infectious nature of incivility itself. Every excess provides the excuse for greater and opposite excess — a search for more vicious put-downs and more startling obscenities. Avoiding this escalation is one of the primary challenges of the schoolyard and one of the important attributes of a citizen. Everyone has grievances; fewer have the courage of manners. All of us need more of it.