Margaret Somerville has responded to Joyce Arthur's column opposing fetal homicide laws.
Here's one excerpt from her excellent rebuttal:
Ms. Arthur recognizes a relationship between the mother and the fetus in speaking of converting that relationship to an adversarial one. Relationships involve more than one person. But, confusingly, Ms. Arthur also takes the position that the mother and fetus are one; that one is the mother; and the mother is the only person who should be recognized in law as a person. (This proposition mirrors the previous legal situation of married women: with marriage, a wife and husband became one person in law and that one was the husband.)