I understand your argument, but (IMHO) it just causes confusion if you try to apply common sense to legal statutes and concepts. (Yes, sure politically one can argue that there's a difference between waiting for someone and running them over intentionally with a car and between abortion, but at the same time others are free to disagree. There's no objective framework for this.)
The fetus is alive. It's a bunch of cells. There's a causal interaction to remove it from the host which makes it a bunch of dead cells.
Legislatig physics is stupid, but what if some state said by law which interpretation of quantum mechanics is the correct one? Stupid, but not much different than building codes. Or say that prions are alive and can run for office... stupid, but there used to be a lot of absurd laws. (If someone works on Saturday they shall be put to death. Sure, what's work? And then there are many many many interpretations of what's work.)
The fetus is alive. It's a bunch of cells. There's a causal interaction to remove it from the host which makes it a bunch of dead cells.
Legislatig physics is stupid, but what if some state said by law which interpretation of quantum mechanics is the correct one? Stupid, but not much different than building codes. Or say that prions are alive and can run for office... stupid, but there used to be a lot of absurd laws. (If someone works on Saturday they shall be put to death. Sure, what's work? And then there are many many many interpretations of what's work.)