No, Virginia, condoms and safe sex are not exactly synonymous. Not necessarily. Not entirely. Not scientifically.

It turns out there may be some things we don't know about condoms, although public health officials are convinced that the devices are the strongest defense we have against the spread of sexually transmitted diseases. The problem is, before the AIDS epidemic, no one ever bothered to do the difficult research needed to confirm that.

And into this gap of knowledge, the opponents of extramarital sex have leapt, with a vengeance.

With GOP hopeful George W. Bush goading them on, social conservatives have found a new way to discourage sex: by promoting the half-true claim that condoms do not really protect against sexually transmitted diseases.

Led by Rep. Tom Coburn of Oklahoma and an Austin, Texas-based medical institute, conservatives convinced the NIH to hold a conference last month revisiting the issue of condom safety, and passed a bill in the House in May that would require condoms to carry a message saying they don't protect against all sexually transmitted diseases.

Meanwhile, as faith-based groups distribute videos and pamphlets to teens depicting the horrors of diseases spread by STDs, the federal government is spending $50 million a year to promote abstinence-only sex education messages. A chunk of that money is going to Texas, which has one of the highest teen pregnancy and STD rates in the country.

Many public health experts and scientists believe the effort to convince people, especially teenagers, that condoms will not protect them against disease is risky and ultimately wrongheaded. They say abstinence education should be mixed with information on how people can use condoms to protect themselves against germs.

But the conservatives' condom campaign is not entirely groundless. The proponents of abstention are absolutely correct in saying the only sex that is certain not to spread venereal disease is no sex at all.

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