The respite will be brief, however, unless President Bush and others who share his concern exercise vigorous, intelligent leadership on this issue. Not all scientists support cloning embryos and killing them to extract their stem cells. But scientists who do support this work are the ones engaging in it, naturally, and the ones who will also, just as naturally, lobby fiercely for ever-increasing federal funding for their work, which they will inevitably portray as the most promising in the field.

The thoughtful and distinguished ethicist, University of Chicago Professor Leon Kass, whom Bush appointed to head his new national council on stem cell work, will have his hands full. Since nobody is talking about nominating me to the council (surprise, surprise), let me take this opportunity to throw in my two cents' worth. Here are some of the questions that haven't even made it onto the moral radar screen for the council's consideration:

EXCESS EMBRYOS. Why are there so many excess embryos floating around anyway? This is not parents' fault. When you divorce baby-making from sex (not my idea, but hey, it happens), it is people in lab coats who decide how many of your eggs will get fertilized and recommend how many get implanted. This is one reason the idea of creating a class of embryos that "would be destroyed anyway" is such a science fiction.

Once you transform human embryos into a medical commodity, there is no way to distinguish between the embryos that are truly "excess" from those manufactured to meet the new taxpayer-financed demand for itsy-bitsy body parts. Maybe it is time to reconsider allowing private enterprise to transform the creation of human life into an industry unregulated, not only for moral but for safety conditions.

When doctors create excess embryos, one of four things happens: Either they are destroyed, they are adopted by other infertile couples, they are left in frozen limbo, or too many are implanted in the mother's womb, leading to expensive multiple births. Except for adoption, none of these are ideal outcomes.

CONSENT. President Bush properly made much of the ethics of experimenting on human beings without their consent. OK, but who can consent for human embryos discarded by their parents? We are really on untrodden ground here.

The Supreme Court has never decided on the legal status of the embryo. Roe v. Wade was based on the right of a woman to autonomy over her body. But in these cases, the embryos are not in a woman's body. When did they become mere property? Can parents who have declined to be an embryo's parents be meaningful custodians of its rights and interests? In what sense are they really the would-be baby's next-of-kin?

PROGRESS. The politicization of scientific research works both ways. Pro-lifers try to steer money away from embryo research; abortion rights advocates try to funnel the federal dough toward the research. Neither are disinterestedly serving science. Government funding can distort scientific priorities; bureaucrats with Ph.D.s are not especially good at picking which lines of research are most promising.

FAIRNESS. If government is going to finance cures for disease, is it a good idea to use techniques that large numbers of people with the relevant diseases find morally repugnant? There are many ways to skin a cat. Why not pour the money into equally promising avenues (adult stem cells, umbilical cord blood, stem cells from miscarriages or premature births) that do not threaten to exclude millions of Americans from enjoying the cure?