Brad De Long on stem cell research :
Why Oh Why Are We Ruled by These Idiots? (Stem Cell Policy)

We are reminded of yet another bad Bush decision of the past, made for no rationale that anybody has ever been able to enunciate:

WSJ.com – Washington Wire: SCIENCE GUYS: Two hundred House members, including conservatives Cunningham and Rohrabacher of California, will ask Bush to relax three-year-old restrictions on embryonic stem-cell research. Backed by celebrity activist Mary Tyler Moore, they’ll argue that there aren’t adequate existing cell lines to support needed research…

No rationale ? I can enunciate it. You don’t have to agree with it, and I’m not sure that I do. But it’s very simple :
Human life begins at conception. Killing people for the benefit of others is wrong.
End of argument.
One can argue with the premise, one can argue on pragmatic grounds, but that is what the argument is.
Some years ago in the UK the Catholic Church stated that a new German Measles ( Rubella ) vaccine should not be used by Catholics. It had been prepared from the tissue of an aborted fetus. One can argue all one wants about the practical implications of this, but it is entirely consistent with Church teaching : Good cannot come from Evil Acts.