It is relevant. For the pro-choicer the unborn is not regarded as a person with equal right to live. That's why the decision is seen as only about one's own body.
I had written, "
And there's another example of the problem with ideas like personhood. The relevant distinction between the two [prematurely born fetus and an unborn fetus]
for the pro-choicer is not that one is a person and the other not."
It doesn't matter to me whether you call the fetus a person or anything else. Its legal status might change, but not the moral status of aborting it. The point is that nothing that you call the fetus makes aborting it unethical. Call it a person. OK, then apparently it is moral to abort presentient persons. Call it a baby. OK, then it is moral to abort presentient babies. Call it a human being. OK, then it is moral to abort human beings. I think you get the point.
What makes the procedure immoral to me is sentience in the fetus, and that's true for non-persons as well. And non-humans. And all other sentient creatures. Was it on this thread that I mentioned that it is moral to throw a chicken egg with a presentient chick embryo in it into a hot frying pan, but not a sentient chicken? Likewise with human beings. Being human changes nothing. Calling a human fetus a person changes nothing, just as calling a chicken or a corporation a person changes nothing morally, just legally. Aborting a chicken embryo granted legal protection from becoming an omelet makes the act illegal, not immoral.
Likewise, whether a fetus is granted rights is a legal matter. You can grant those same rights to the chicken embryo in the egg if you like, but that doesn't change the moral judgment regarding aborting it at all, just the legal consequences of acting on those moral judgments.
For me, the entire question revolves around whether aborting presentient fetuses is immoral, and if not, who gets to decide if the pregnancy comes to term. All of the rest of these considerations regarding nomenclature aren't relevant to me.
Nor are they relevant to the anti-choice crowd despite their willingness to deploy them. You won't find them changing their positions based in what a fetus is called, either. Pass a law saying that fetuses are not persons and are not entitled to the protections of people, and they will ignore that and continue to call the procedure immoral.
I understand that these are probably not your values, and my telling you that they are mine doesn't change your view on abortion. Please recognize that the reverse is true as well. The values of the anti-choice movement are not my values, and nothing changes however many times they repeat that they are their values. Yes, many people find abortion unacceptable. What the rest are telling them is that is not how they feel, and repeating how much one disapproves of abortion gets no more response than to not have one if that's how you feel.