Presidential ambiguities

Ben Z. suggests that there is no ambiguity in the terms "sexual relations" and "is," while torture is really hard to define. I think in the case of sex and the case of torture there are unambiguous paradigm cases, and then there are ambiguous cases. As I showed in this previous post, there is an ambiguity related to the word "is." A critic of Clinton should not say that there are no ambiguities in the uses of these terms, what the critic should say, with some justification, is that he is using the ambiguity in the use of the term in general to mask the fact that in the relevant case, the ambiguity is nonexistent. But can't the same thing be said about Bush and the secret prisons?