MUCH OF THE CURRENT DEBATE over what is generally known as therapeutic cloning–that is, somatic cell nuclear transfer (SCNT) cloning conducted for research purposes rather than reproduction–centers on the nature of the thing that is created by the cloning process. Until recently, this issue wasn’t controversial: Cloning, it was widely agreed, created a new human embryo.

Thus, in 1997, President Bill Clinton’s National Bioethics Advisory Commission’s report on the ethical issues involved in human cloning stated: “The Commission began its discussion fully recognizing that any effort in humans to transfer a somatic cell nucleus into an enucleated egg [SCNT] involves the creation of an embryo.”