A few replies to these very interesting comments:
One comment asks whether, if people don't have free will in some strong sense, they can object to a law--say a ban on smoking--that restricts "freedom." But let me say first that I don't object to rhetorical flourishes, and so to marching under the "freedom" banner when defending a right to be left alone by the government in particular areas of liberty. In fact I find Mill's libertarian principle extremely attractive. But I don't find it attractive because I think I have free will in some strong sense of metaphysical autonomy--of exemption from cause and effect--but because I don't expect to be made better off by being told not to do things by government officials who have a much less exact knowledge of my utility function than I do. This response also relates to a comment that asked whether one can rationally complain about being "coerced" to surrender one's watch to a thief who says your watch or your life, if one has no free will. My answer is yes. Even if everything a person does is in a sense coerced, if only by character, upbringing, and other internal-seeming forms of coercion, there are certain forms of coercion that we would very much like to do without, even if the only consequence is to allow other forces to determine what, say, shall happen to my watch. Of course to speak of character as "coercive" is something of an abuse of language; and it is no part of my purpose to reform language. I assume that moralistic rhetoric, including the language of free will, serves a social function. It serves that function whether or not there is "free will" in a sense that engages the interest of philosophers and theologians.
One comment points out that my discussion of criminal responsibility treats the function of the criminal law as deterrence; it is also preventive. But there no interesting question of responsibility arises, because when crime is prevented by imprisonment there is no intervention in the thinking process and therefore no issue of free will. It is when the threat of punishment enters into the calculations and emotions that determine action that we are treating the potential criminal as a "responsible" being, meaning only by that that he has the mental capacity to add the threat to the implicit cost-benefit analysis that determines his conduct.