During the next 35 years, the traditional view of the sanctity of human life will collapse under pressure from scientific, technological, and demographic developments. By 2040, it may be that only a rump of hard-core, know-nothing religious fundamentalists will defend the view that every human life, from conception to death, is sacrosanct. In retrospect, 2005 may be seen as the year in which that position became untenable. American conservatives have for several years been in the awkward position of defending a federal funding ban on creating new embryos for research that prevents U.S. scientists from leading an area of biomedical...