Most non-religious seem to agree there is a difference between a person and a potential person (I’d ask Christians when they think the soul enters the body, if identical twins share a single soul etc.). Given that there is a continuum between a zygote (the single cell fertilized egg) and a human being, there is no bright line differentiating the justifiable from the immoral. We shouldn’t forget that this debate is taking place in a context in which religious ideologues are trying to pass laws limiting abortion without exception for the woman’s health; there is no logical justification for privileging the life of a potential person over the life of an existing woman. There is a statistical point in development before birth beyond which we should do everything that we can to save the life of the child (excepting of course in cases where the life of the mother is threatened). The question is what science has to say about the rate of fetal development and where to use the force of law to draw a legal line in the sand. “[S]cientific consensus . . . holds that fetuses are unlikely to be able to feel pain before 26 weeks.”
“In most . . . states, abortions are banned only when a fetus is deemed to be old and mature enough to survive outside the womb, typically any time beyond 22 to 23 weeks.”
As technology develops there will be more answers and more questions.