SOCIAL conservatism may have found its nemesis in economic conservatism, and a tiny white pill called RU 486.

Social conservatives believe the rights of an unborn baby supercede any right to privacy, and argue against any constitutional guarantee to a safe abortion. Economic conservatives laud the powers of a market economy--where demand for a product creates incentives for its supply.

These beliefs will soon collide because of RU 486--an abortion-inducing pill that can be taken in the privacy of your own home. The pill, now legal in France but not approved by the Food and Drug Administration (FDA) in the United States, has already been called "chemical warfare against unborn babies" by extreme anti-abortionists.

Such metaphorical attacks against RU 486 and attempts by the FDA to stonewall its legalization, however, will not prevent the pill's distribution in America. This country cannot prevent tons of cocaine from entering our ports from South American countries. It seems inconceiveable that we could prevent tiny pills that look like Tylenol from entering our nation via the Concord.

ANTI-ABORTIONISTS are still making an international fuss over RU 486. In France, the pharmaceutical company Roussel Uclaf--which made the pill--almost stopped its distribution because of anti-abortion pressure. The company then reversed its decision in the face of pro-choice protests. RU 486 is now widely distributed in France, and is headed toward other Western European countries.

But the United States still has a long way to go. Several pharamaceutical firms, despite pressure and threats of boycotts, plan to assess the risks of drug's abortifacient effects. Others hope to test the drug for its medical effects, unrelated to abortion, on diseases ranging from breast cancer to AIDS.

The FDA--under heavy political pressures--intends to keep RU 486 out of circulation, for whatever purposes. When the FDA loosened restrictions on unapproved drugs for the personal use of desperate AIDS patients in 1988, the department signalled out RU 486 with an "import alert" barring it from any such consideration.

THE legalization of RU 486 will alter the moral underpinnings of both sides of the debate. Anti-abortionists will have little effectiveness in convincing us that a blood clot is a fetus. Pro-choicers will be just as ineffective in arguing that regulation of abortions will force women into back-alleys.

Instead this will force them into illegal drug trading. The case of illegal narcotics proves that where there is a demand for an illicit drug, there will always be a supply.

Despite Drug Czar William Bennett's claims that military action can stop trade in illegal narcotics, drug trafficking increased last year. Bennett underestimated the lengths to which suppliers will go to fill the demand.

And that demand may be just as great for RU 486. The pill is safer, faster, and less expensive than abortion surgery.

Whether surgical abortions remain legal or not, RU 486 is a reality. Now, the question is whether it will be taken legally and with recommended medical attention, or illegally and with a risk of harm.

Complex moral arguments notwithstanding, it's simple economics.