Film-maker Michael Moore has apparently praised the gulf weather for its chance of disrupting the Republican convention: “This hurricane is proof that there is a god in heaven.” Another low point in politics, though possibly one that could be passed off with a laugh—a partisan irony, rather than a serious derangement. But over on the leftist Daily Kos website, there is a post that sinks much lower—so low that it caused many of the commentators to denounce it. Which led another commentator to make this remark: I am prepared to do whatever is necessary to destroy the Republican Party as...