Consistent bioethical standards are the only way to control cloning research

Instead, he intends to use cloned embryos to produce embryonic stem cell lines which might ultimately yield cures for diseases such as Alzheimer’s and Parkinson’s disease and diabetes.

But no matter how much Hwang and other scientists in favour of therapeutic cloning try to distance themselves from reproductive cloning, their ethical scruples are unconvincing.

They all agree that it is currently a threat to the health of human babies, as most cloned animals are born with significant abnormalities. But if these health problems can be overcome, what then?

Most scientists are quick to call reproductive cloning “dangerous” but are very loath to denounce it as intrinsically immoral. Last year, for instance, more than 60 of the world's leading science academies, including Australia’s, called for an international ban on reproductive cloning. But they said it "should be reviewed periodically in the light of scientific and social developments".

In other words, they were hedging their bets. If reproductive cloning ever becomes safe, it might become necessary to make it ethical as well.

Cynical? Of course, but Hwang’s ethics and the fulsome support given to his work by America’s leading science group, invites cynicism.

This time they turned a blind eye to unethical exploitation of Korean women to advance their pet project of therapeutic cloning. When reproductive cloning is no longer dangerous there is little doubt that their ethics will be just as flexible.