It strikes me that some potential readers may feel dismayed at my advocacy of a recognizably pro-life position on abortion rights when they have been promised progressive politics. If I have a base among my two readers yet I can throw some red meat at it later but for now I don't see any contradiction between the two positions. I identify myself as progressive in the same spirit (with due respect) that Chesterton called himself a liberal. He also named St. Thomas (and Jesus, and Dickens) among history's greatest liberals. I think that Chesterton and I both mean that to be progressive, or liberal, is to be dedicated to the goodness and potential of the human species - that the created order is really good, and human beings are really good with the potential to get even better. This stands in distinct opposition to the false liberalism of Hobbes, for instance, for whom no real progress is possible. I believe that true rationality, i.e. the love of the true, the good, and the beautiful is the transcendent goal of human history (albeit always only partial and known as fully through its absence as its presence.)
It is this perspective which prevents me from accepting the reductionist and nihilistic logic of "choice" as it is applied to abortion rights. I have never understood how the phrase "a woman's right to choose..." can be abbreviated. To choose what? Fries with that? Choice is not an intrinsic good, and freedom doesn't occur in a vacuum. It may be the case that fetuses never feel or experience anything, but if so, I believe that is strongly relevant to the matter of abortion. This puts me on the wrong side of abortion rights advocates, who believe that it makes no difference one way or another.
What this shows is that on the position of abortion, science and Christian ethics converge. Both compel me to recognize the potential claim that another (even a theoretical other, such as a member of a future generation) makes on my freedom. I can't dispose of this obligation, and I can't ignore it - I'm already bound by it as soon as I recognize it. Science makes that other present to me and won't let me go until I acknowlege its legitimate authority. There's no freedom without relation, and no such thing as progress for one individual alone.