If The Onion didn’t exist, it would be necessary to invent it. The self-described ‘omnipotent’ purveyor of current-events satire may not be (as another motto claims) ‘America’s finest news source.’ But it does have a good claim to the nation’s nicest anatomist of political folly (using, I hasten to add, that capacious word ‘nice’ not in the sense of ‘kind, pleasant’ but ‘precise, exact, fine’).