Susan Dentzer provides some background on President Bush's long-awaited decision on stem cell research.
MARGARET WARNER: For months, the country has been awaiting the President's decision on an issue where science, ethics and politics collide. We get a preview from Susan Dentzer of our health unit, a partnership with the Henry J. Kaiser Family Foundation.
SUSAN DENTZER: Speaking at President Bush's Texas ranch today, White House Spokesman Scott McClellan said the President would announce his long-awaited decision on stem cell research in a televised address to the nation tonight.
SCOTT McCLELLAN: This is a serious, difficult issue that the President has approached in a deliberate and thoughtful manner over the course of the last several weeks, and since the beginning of this administration. The President has carefully considered all the scientific and ethical issues involved, and he wants to share his decision directly with the American people and why he reached the decision that he reached.
SUSAN DENTZER: That decision is whether or not to allow federal funding of research on human embryonic stem cells. These are the building-block cells that make up a human embryo when it is just several days old. The stem cells ultimately develop into all of the specialized cells and tissues that make up a human being, and unlocking the secrets of that process could lead to revolutionary treatments for a range of devastating diseases, from Alzheimer's to Parkinson's to cancer.
DR. ERIC WIDRA: When we can learn what turns cells on to go down one path of development or another, it becomes an incredibly powerful tool to understand human disease and to provide treatment.
SUSAN DENTZER: At the same time, there's also been growing interest in the potential of stem cells derived from adults. These are found in tissue like bone marrow and the brain. But, as yet, it's not clear whether such cells will prove as capable as embryonic cells at differentiating into all the body's specialized cells and tissues. Amid all the scientific excitement over stem cell research have come profound ethical concerns. That's because embryonic stem cells can only be obtained by destroying embryos, many of them left unused after having been created through fertility treatments.
RANDALL TERRY: Mr. Bush, you have a duty before god: These human embryos are made in the image of God. You must be their protector not their betrayer.
SUSAN DENTZER: For the better part of a decade, Congress has each year voted to renew a ban on federal funding for any research that destroys an embryo. But last year, the Clinton administration issued guidelines allowing some federal funding of stem cell research to proceed; it said that research could only be carried out on stem cells already obtained by non-government-funded entities. During last year's Presidential campaign, then-candidate Bush implied that he would reverse the Clinton guidelines in an effort to build support among right-to-life groups. When he took office earlier this year, he formally put those guidelines on hold and wrote to one right-to-life group that he "opposed federal funding for stem cell research that destroys living human embryos." But he added that he supported other aspects of stem cell research, including work on stem cells derived from adults. The issue figured prominently in the President's meeting with Pope John Paul II in Italy last month.
POPE JOHN PAUL II: (June 23) A free and virtuous society which America aspires to be must reject practices that devalue and violate human life.
SUSAN DENTZER: After the pope urged him to bar funding, the President spoke to the press.
PRESIDENT GEORGE W. BUSH: I take this issue very seriously, because it is an issue that, on the one hand, deals with such hope, hope that perhaps through research and development we'll be able to save lives. It's also an issue that has got serious moral implications, and our nation must think carefully before we proceed. Therefore, my process has been, frankly, unusually deliberative for my administration. I'm taking my time.
SUSAN DENTZER: Back in Washington, some prominent conservatives with strong right-to-life credentials came out in favor of federal funding of stem cell research.
SEN. ORRIN HATCH: And I came to the conclusion that if we want to extend life and facilitate life, then we should take these embryonic stem cells that are going to be discarded anyway, and we ought to use those in the best interest of mankind.
SPOKESPERSON: Even though the promise of stem cell research has broad support in Washington...
SUSAN DENTZER: As polls showed a majority of the public in favor of stem cell research, disease research advocates stepped up the pressure.
SPOKESPERSON: Insulin keeps her alive, but stem cell research could cure devastating diseases like juvenile diabetes, giving Samantha hope for a long and healthy life.
SUSAN DENTZER: Today Health and Human Services Secretary Tommy Thompson, who's in the past advocated federal funding of embryonic stem cell research, spoke on ABC's "Good Morning America."
TOMMY THOMPSON: I am fairly comfortable with the decision that the President is going to make, and I'm very confident that the American people will be as well.
SUSAN DENTZER: But in the meantime, congressional supporters of stem cell research said today that the President wouldn't necessarily have the last word on the issue.
SEN. TOM DASCHLE: If the President comes out with another decision short of the one that we hope he will make, it would be my expectation that we will schedule legislation sometime this fall to have the debate and the opportunity to fully fund stem cell research as, I think, a strong bipartisan majority in the Senate would support.
SUSAN DENTZER: The President's speech is to be broadcast live from his Texas ranch at 9:00 tonight.