I think it is just an attempt to eventually over-rule Roe v. Wade by means of laws that skirt the issue.
Currently, the fetal homicide laws do not apply to legal abortion or in instances where the life of the fetus could not be maintained artificially ex utero.
Its a touchy issue. On one hand, you have a woman kicked in the stomach and her baby dies, so you charge the person with homicide. But all you would have to do to ban abortion would be to argue that abortion is a violent act against a pregnant woman, or an act of homicide against the fetus.
I don't support them, honestly. I think that if society is ok with women killing fetuses, what is different about a woman being kicked in the stomach and the fetus dying? You can't argue that the unwanted fetus was a mass of cells, but the wanted fetus was a chid. That is a contradiction.
So I am all in favor of people being charged with assault against the pregnant woman, but homicide against the fetus? I don't think that is fair. So no, I do not think it should be a capital offense since there is nothing particularly notable that distinguishes kicking a woman in the stomach from a legal abortion except a doctor's office.