三、 A decade ago, James A. Thomson was the first to isolate human embryonic stemcells. Last week, he announced one of the great scientific breakthroughs since thediscovery of DNA: an embryo-free way to produce genetically matched stem cells.        Even a scientist who cares not a whit about the morality of embryo destruction willadopt this technique because it is so simple and powerful.        The embryonic stem cell debateis over.This allows a bit of reflection on the storm that has raged ever since the August 2001announcement of President Bush's stem cell policy. The verdict is clear: Rarely has apresident — so vilified for a moral stance — been so thoroughly vindicated.