Is it because the embryo and fetus are developmentally less advanced, that they’re considered mere “human beings”, rather than elevated to the protective realm of personhood?

It’s that something without a fully interconnected brain can’t be conscious or aware of anything.

If this is the case, then, obviously, this logic would entail that, once the fetus is born, it still wouldn’t be a “person” since the newborn, and preborn, are not qualitatively that different.

The nerve pathways and brain structures sufficient to be aware of something as basic as pain actually hook up and start operating sometime between 20 and 22 weeks.

The courts decision would seem to provide then, a rationale for infanticide.

Perhaps a better approach would be to not try and make an arbitrary distinction between being a human being and a human person?

As Richard John Neuhaus has accurately asserted,(to paraphrase him) the fetus looks just like what a human is supposed to look like, at that stage. And to expand on this, at every point in human development, the human has traits that are distinctive to that particular stage.

Presumably, this court is assuming the validity of personhood being the point where the law protects humans, and that, to be a person, one must possess certain traits. What are these traits, and what argument or arguments is this court using to convince us that these traits bestow personhood on someone?

Bret,

And yet, it was maintained by the US Court of Appeals for the Eight Circuit in upholding a part of South Dakota’s abortion law.

The human being advisory requires that the pregnant woman be told that an abortion will “terminate the life of a whole, separate, unique, living human being.” The en banc court held that this provision withstood a First Amendment challenge because it must be read together with the Act’s definition of human being. 530 F.3d at 735. Because “human being” has only a “narrow, species-based” meaning in this context, the advisory conveys “scientific[] and factual[]” information that “should be clear in context to a physician.” Id. at 736. Planned Parenthood now argues that in focusing on the statutory definition of “human being” in § 34-23A-1(4), Rounds implicitly held that South Dakota may not compel doctors to use the exact language of the human being advisory contained in § 34-23A-10.1(1)(b). South Dakota responds that Rounds upheld that human being advisory unconditionally.

The statute in question had the following definition:

“Human being,” an individual living member of the species of Homo sapiens, including the unborn human being during the entire embryonic and fetal ages from fertilization to full gestation

To simplify somewhat, the court found that it was acceptable to tell a woman seeking an abortion that the abortion would kill a human being, because the statute’s definition of human being did not, in fact, indicate that a human being was a human person.

Those who support abortion, and are sufficiently informed vis a vis human biology, must make a distinction between being a human being and a human person, and attempt to argue that the unborn are not human persons, and only human persons should be protected by law. This distinction cannot be rationally maintained.