In her last column, Boston Globe columnist Ellen Goodman wrote: "Let's just say that global warming deniers are now on a par with Holocaust deniers . . . " This is worthy of some analysis. First, it reflects a major difference between the way in which the Left and Right tend to view each other. With a few exceptions, those on the Left tend to view their ideological adversaries as bad people, i.e., people with bad intentions, while those on the Right tend to view their adversaries as wrong, perhaps even dangerous, but not usually as bad. Those who deny...