Cathryn, you've made this assertion several times on this thread:
How are you going to argue your moral belief that abortion is wrong with, say, a hardcore moral relativist?
I spend a whole lot of time in abortion and related life issue discussions. It is not the hardcore whom we must convert in order to bring a legal end to abortion on demand (we will never outlaw the practice compeltely because it is proper to end a pregnancy when a woman's life is endnagered by an unviable child in her womb ... right of self defense). It is the vast moderate American public who have purposely avoided becoming interested in the debate over abortion and who by and large have little or no facts regarding life before birth upon which to call when the issue of voting for abortion champions or abortion opponents comes up. It is to that vast moderate public that your combined logical and moral approach suggested will have the most positive impact.
BTW, great essay; thought provoking, obviously.