MOTIVATION: CRITICS CHARGE U.S. AID IS FUELED BY FEAR OF COLOMBIA'S REBELS.

IT IS NOT VIETNAM, nor will it become so. But once again the United States
is preparing to commit lots of cash, military hardware and advisers to a
battle in a foreign jungle.

This one is in southern Colombia, where an embattled president, Andres
Pastrana, faces daunting problems. These include left-wing guerrillas and
right-wing paramilitaries.

Political violence caused almost 300,000 Colombians to flee their homes last
year; the better-off have been terrorized by kidnapping and extortion.

The country is also home to the world's biggest illegal drug industry: It
accounts for about 80 percent of the cocaine and some of the heroin imported
by the United States, and has displaced Peru as the world's main source of
coca, the raw material for cocaine.

This is the main front in the developed world's war against the supply of
drugs. And, to make matters worse, Colombia's economy is reeling from its
worst slump since the 1930s.

On taking office in 1998, Pastrana boldly launched peace talks with the
46ARC, the largest guerrilla group. But they have moved slowly. The war
continues, amid widespread skepticism about the FARC's intentions.

At the same time, Pastrana has turned to the United States for help.
President Clinton is sympathetic, and Congress is debating an administration
request for more aid, which would take total American assistance to Colombia
to $1.6 billion over the next two years.

Pastrana leads a democracy, albeit an imperfect one, and deserves
international support. But the proposed aid is ambiguous in purpose, and its
results may disappoint.

The largest chunk is to set up and train three special anti-drug battalions,
equipped with 63 helicopters, including 30 fast, modern Black Hawks.

Their mission is to ``push into the coca-growing regions of southern
Colombia,'' in mountainous jungles now controlled by the FARC. Once secured,
the police would go in to wipe out the coca plantations.

Its backers present this as a plan to stanch the flow of drugs to the United
States. But the motivation seems to be a fear that the FARC's insurgency is
now out of control, and is a threat to other countries in the region.

In practice, the new battalions' target will be the FARC. Because the FARC
gets lots of money (perhaps as much as $500 million a year) from taxing and
protecting the drug trade, this new southern push would not only help to
prosecute the international war on drugs but also weaken the guerrillas,
persuading them to seek peace.

That, at least, is the theory. Yet if the main aim were to support the
pursuit of peace, the aid proposal might look very different.

The belief runs deep that paramilitary violence will hasten peace. In fact,
it does the opposite. It is as unacceptable as the violence of the
guerrillas. Yet the American aid proposal looks as if it will merely bolt
three shiny new anti-drug battalions on to an abusive and unreformed
military force.

Aiding the Colombian police has been adopted as a political cause by a group
of congressional Republicans who believe that one of the cheaper and more
effective ways to deal with the United States' addiction to drugs is to stop
their production at source.

That approach is also reflected in the annual ``certification'' process,
which this week again saw the United States stand in judgment over its
neighbors' anti-drug efforts.

Belief in supply-side remedies has come to be shared by some officials in
the Clinton administration.

They argue that the sharp fall in coca production in Peru and Bolivia in
recent years is proof that a combination of stepped-up repression and
programs to help former coca farmers can eliminate coca in those
countries -- and in Colombia.

It is a heady vision, but a flawed one. In fact, these policies have fueled
Colombia's conflict.

The increase in Colombian coca (and thus in the FARC's income) is a direct
consequence of its reduction elsewhere. That is just the latest example of
the ``balloon'' effect: Squeeze the drug industry at one point, and it
reappears somewhere else.

Already drug-trafficking gangs, with all their corruption and violence, have
spread across Latin America from Mexico to Brazil. The reason is elementary.
Demand calls forth supply.

Prohibition and repression merely increase the price; and, where cocaine is
concerned, they have failed to increase it enough to have any significant
effect in reducing consumption.

After more than a decade of the United States' war against cocaine at the
source, the price of the drug in the United States remains stable, the
supply abundant. The number of hard-core takers remains stable, too,
although casual consumption has declined since the mid-1980s.

Latin Americans pay a high price for the drug trade: It corrupts their
societies from top to bottom. If this price is ever to be reduced, Americans
will have to look not just at the supply but also at the demand for drugs.

That means they will have to consider alternative policies at home, even
decriminalization. This is a war that will not be won with helicopters.

This editorial appeared in The Economist magazine.