It's going to get a lot more complicated as research progresses. Personally, I have no problem at all with early abortion, but even if I did, I couldn't possibly consider an embryo at this stage to be "a person". At that stage, the embryo can still be split in two, either naturally or artificially, and become twins (or even split again and become even more separate organisms). And two embryos at this stage can be squished together and become a single organism (this happens naturally, though apparently not as often as twinning -- but it's not clear if the detection rate accounts for a lot of the difference; there have been plenty of people discovered to be genetic mosaics in adulthood, when there had been no outward indication of this all their lives, and never would have been if some genetic test hadn't been performed for some other reason). And left on its own, created the natural way inside a woman's body, such an embryo only has about a 20% chance of ever developing into a baby anyway.
Right now, researchers aren't able to get a single cell at this stage to develop into a normal embryo with potential to continue developing into a baby (though getting 2 adjacent cells to do that has been possible). But that's likely to change, and I suspect that within 10 years or so, if not sooner, they'll be able to get a single embryonic cell to develop into a baby. Which begs two questions" 1) if you pluck one cell from an embryo and DON'T coax it into developing into a separate twin embryo, did you "kill a baby"? And for that matter, if you had a healthy 8 cell embryo in your petri dish, and just popped it into the mother as is, rather than splitting it up so it could become 8 babies, did you "kill 7 babies"?
There will always be people who trouble themselves over these questions. I'm not one of them, as I don't see the point of spending my life bemoaning an inexhaustible list of what-if's. What if a 13 year old girl whose parents wouldn't let her go over to her 14 year old boyfriend's house when his parents weren't home, HAD let her? A sperm might have fertilized an egg, and the resulting zygote might have developed into a wonderful baby who grew up and made valuable contributions to society. But they DID keep her home, thereby interfering with very natural processes and instincts, and that zygote was never formed, and the baby was never born, and never grew up to do anything.
Should I be sad or angry about this? Should I be protesting parental interference with natural adolescent instincts? Should I be urging people who DID get conceived and born that way to run around giving media interviews and testifying before legislatures, asking people "How can you say I shouldn't have been allowed to be conceived and be born?", and pushing legislation that would prohibit parents from interfering with their adolescents' sexual activity? Of course not. And I'm not going to worry about what happens to any 8-celled embryos either.
And you needn't make any effort in this regard. Other people will explore the what-ifs, I am sure.
What if a 13 year old girl whose parents wouldn't let her go over to her 14 year old boyfriend's house when his parents weren't home, HAD let her? A sperm might have fertilized an egg, and the resulting zygote might have developed into a wonderful baby who grew up and made valuable contributions to society. But they DID keep her home, thereby interfering with very natural processes and instincts, and that zygote was never formed, and the baby was never born, and never grew up to do anything.
Should I be sad or angry about this? Should I be protesting parental interference with natural adolescent instincts? Should I be urging people who DID get conceived and born that way to run around giving media interviews and testifying before legislatures, asking people "How can you say I shouldn't have been allowed to be conceived and be born?", and pushing legislation that would prohibit parents from interfering with their adolescents' sexual activity?
You are very skilled at conjuring up long lists of what-ifs.