Indeed. The disagreement over abortion is, roughly, whether killing a human fetus should ever be legal. The disagreement is hard to resolve because it’s not clear which principles to apply, so that arguments pro or con can take on a semantic flavor, but there’s nothing semantic about the underlying issue. (It might be that the author harbors some feeling that all ethical questions are merely semantic; this is putting a lot of weight on a distinction which became discredited in 1951).
I mean, I think there _is_ some semantic debate, in that there are always semantic debates about what is life and what isn't on the edges (see the endless rather tedious argument about whether viruses, or, more esoterically, mitochondria, are life whenever anyone brings it up), but it's largely irrelevant to the actual question.
