Regarding Sunday’s shooting of abortion-providing doctor George Tiller, in the lobby of his church, by a professed pro-lifer, Slacktivist says it best, reflecting on a similar shooting, and the similar responses it elicited, in 1994:
These were groups that routinely spoke of abortion as “murder” or “mass-murder,” and that routinely spoke of legalized abortion as an “American Holocaust.” They had, for years, been using precisely the same rhetoric and making exactly the same arguments that Paul Hill was now using to attempt to justify his  double homicide.
Those groups’ condemnations of Paul Hill then — like their condemnations of [Tiller’s alleged killer] Scott Roeder now — ring hollow. Such condemnations seem to be self-refuting. How can they condemn men like Hill or Roeder just for taking their own arguments seriously?
Thought experiment: if anti-abortion groups were Muslim and said the things they said, and a professed Muslim followed through and shot someone, would it even occur to the American political classes to take said groups’ word that they never meant to call for actual violence?