Enlarge By Steve Ruark, AP The U.S. Conference of Catholic Bishops, which held a semi-annual meeting this month in Baltimore, says lifting a ban on funding for stem cell research would alienate millions. WASHINGTON — President-elect Barack Obama could reignite an emotional national debate over the promise and the perils of medical research using cells taken from human embryos. The United States Conference of Catholic Bishops is warning that Obama will alienate millions, and abortion opponents are bracing for a fight. Medical researchers, meanwhile, are rejoicing at the prospect of freedom from a government policy they say has stymied efforts to develop life-saving treatments. Like previous presidents, Obama is expected to issue a flurry of executive orders after he takes office Jan. 20. Some could reverse Bush administration policies; others could promote his own. Ending a ban on government funding for research using embryonic stem cells would be among the most controversial. "The question is, does the Bush policy get replaced with the law of the jungle" where scientists can create and clone human embryos for the sole purpose of studying their cells and then destroying them, asks Richard Doerflinger, the bishops conference's associate director of the Secretariat for Pro-Life Activities. "We are very concerned about it as a moral issue." Samuel Casey of Advocates International, a Christian law firm that opposes abortion rights, says a change in the Bush policy "would give a green light to the kind of eugenic human experiments that people think of when they talk about cloning." Scientists say cells taken from human embryos offer the most promise of being used to develop therapies for Parkinson's, diabetes and other diseases. Some scientists have found cells taken from adults also have lifesaving potential. "Current policy has depressed the field" of research and caused an exodus of scientists from the United States to other countries where such research is flourishing, University of Iowa researcher Nicholas Zavazava says. But "we are a big country; we ought to be able to roll things back." States such as California have gone ahead and funded stem cell research on their own in the absence of federal money. Obama's campaign promised broad support for stem cell research. His website says he "believes we owe it to the American public to explore the potential of stem cells." After the election, John Podesta, chief of Obama's transition team, said aides are reviewing a host of areas where Obama might act fast, including on federal funding for research using embryonic stem cells. Controversy surrounding the research has simmered since 2001. That's when President Bush imposed the funding ban during his first prime-time televised address to the nation. His decision, a month before the 9/11 attacks, was regarded at the time as likely to be one of the most important of his presidency. Abortion opponents, Catholics and many political conservatives were elated. Others, including former first lady Nancy Reagan and California's Republican governor, Arnold Schwarzenegger, support the research and have pushed for it ever since. Twice during his presidency, Bush has vetoed bills passed by Congress that would have lifted restrictions on stem cell research. If Obama issues an order reversing the ban, Congress will have to act again — and House Speaker Nancy Pelosi has suggested it will. A law on the books since 1996 bans funding of research that harms embryos and would prevent funding for research even on cells from embryos slated to be discarded by fertility clinics. Opponents of the research have no recourse against an executive order from the White House aimed at releasing tens of millions of dollars. But they can do battle on Capitol Hill. Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more