[Usenet] "As a Usenet discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches one." There is a tradition in many groups that, once this occurs, that thread is over, and whoever mentioned the Nazis has automatically lost whatever argument was in progress. Godwin's Law thus practically guarantees the existence of an upper bound on thread length in those groups.
You can throw around the "one-issue" epithet all you like, but neither of you answered the question. So let me put it another way--are Americans "one-issue" voters if they won't elect someone who praises Osama bin Laden and the Sept. 11 attacks? Are they one-issue voters if they won't support someone who helps fund terrorists?