It would have been much easier for President Bush to have a policy that simply said no to embryonic stem cell research. The more complicated (and difficult to explain) course he chose was grounded in the notion that the science does have real potential (as he explained in originally setting out the policy), but that this potential doesn't make it any less unethical to destroy human embryos for research. What was needed was an approach that took account of both, and he offered one.

As to whether President Bush had anything to do with advances like this cell reprogramming work, I think it's actually a rather complicated question. I was the White House domestic policy staffer charged with the stem cell issue (among other issues, thankfully) in the first two years of the second term, and I had served as executive director of the president's council on bioethics for much of the first term. So I had something of an inside view of that part of the story.

To my knowledge, the president was first informed about the potential of alternative sources of pluripotent cells when I briefed him in May of 2005 on the contents of a bioethics council report on the subject. We discussed reprogramming in particular detail; he was very curious to know whether the technique was really plausible scientifically, and I told him that based on many conversations with researchers and experts, it seemed so, but would take time. "Be sure we're helping," he said.

From then on, we in the administration tracked the work carefully, and sought to help where we could-- though that wasn't much. The NIH could already fund such work, and was doing so, though they were open to ways of doing more to help, and they did get more active in encouraging it. President Bush also started talking publicly about the potential of alternatives, beginning in May of 2005. By the summer of 2006, he was speaking quite specifically about reprogramming skin cells to function like embryonic stem cells. He also met personally with several researchers involved in developing such alternatives, and we on his staff talked with many more. In 2006, we sought legislation specifically to advance this kind of work. It passed the Senate (unanimously) but not the House, and in 2007 (after another failed effort to pass the bill) President Bush signed an executive order to offer more support himself.

But that said, the researchers clearly didn't need us to tell them how promising this work was. They didn't share President Bush's ethical concerns, but they knew somatic cell reprogramming would be very useful and important scientifically, and also that it would allow their work to receive unambiguous and wholehearted public support, and would take them out of the political crosshairs. I think our work, in the White House, contributed mostly to making that latter point plain -- the scientists wanted to get here for their own reasons, but we helped them see that there would be additional serious advantages to doing so. It certainly did help persuade some of them to take it up -- I know that much for a fact. But did it simply facilitate this advance? I think it helped at the edges (and the general opposition of pro-lifers to embryo destructive research did as well) but wasn't the defining force.

I think the president deserves enormous credit for standing firm on the ethical principle here, against massive (and often totally irresponsible) political pressure. That was important and right in itself, and it also did help to nudge stem cell research in the right direction. But as a matter of moral and political leadership, the first part was much more important than the second, and was also what made the second possible. Science can be flexible, ethics must be firm, and the combination can help avert a collision.

We have arrived at this particular most welcome conclusion to the stem cell debate thanks to the work of creative stem cell scientists. But we have, in the meantime, lived up to our commitment to human equality and dignity and not violated a crucial ethical boundary thanks to the leadership of George W. Bush. Hats off to both.