If it were, then that would suggest a volitional intelligence on the part of the foetus which would make it unquestionably human, even in the Singerist sense, and it would have a corresponding right not to have its life involuntarily terminated. His argument is similar to the bizarre libertarian argument that the pregnant woman has the right to an abortion because the foetus did not sign a lease agreement, and even if it did, it is behind with the rent. But the mother would like to do other things, follow other paths, and so since she has the right to do these things, she takes a knife out of the kitchen drawer and kills her son. Even here, the comparison is not exact, because she could consider that she has done her bit, and leave the son to the care of another relative. The pregnant woman cannot move the foetus to another uterus.
Pregnancy is a quite unique situation.
There are no valid metaphors which can be employed by either side in the abortion question. In a free society, with a separation of church and state, it cannot be a religious question. The secular law never involves itself with the soul , or salvation , and it is quite right not to do so. These matters are none of its business.