Politicians: plz stop using "evil" kthxbai
While I'm on the subject of John McCain: the use of "evil" in a political context is rarely edifying, and everybody needs to knock it off. "Evil" is a moral, not political or ideological, term, and to introduce it into political discourse is to cast the discussion in stark, Manichean terms. True, it is an antonym to "good", but since "good" is a heavily overloaded term, it has many antonyms. By definition, evil is "profoundly immoral and malevolent", and when we, for example, brand Iran's president as such, all we do is preclude the possibility of diplomacy. You can't negotiate with evil, you can't contain evil, you can only annihilate it.
Bush's speechwriters famously inserted "evil" into the mass political consciousness of America through the introduction of those infamous supervillains the Axis of Evil. By dint of sheer repetition we've all forgotten how impossibly stupid it sounds, and how it makes the US look like it's governed by a bunch of 8-year-olds. In effect, it's become another phrase on the Godwin's Law blacklist, because any mention of evil in a foreign policy discussion is sure to be followed by a heated and completely useless argument over how much people who are against eradicating the evil must have loved Hitler.
The United States has many real, dangerous enemies, and the geopolitical environment is fraught. The discussion of the whos and hows and whys of this enmity, and the danger it entails, is a proper debate for politicians and presidential candidates to be having. Tossing around stark and (by definition) immutable moral judgment stifles that discussion and drains it of nuance. The US needs to have a debate about our duties and responsibilities in the rest of the world. That's not going to happen if we're viewing the world outside our borders in terms of angels and devils.