As President Bush swung through Colombia during a South American tour this week, critics say that Plan Colombia, the administration's centerpiece supply-reduction program in the region, is failing, the San Francisco Chronicle reported March 11.

From Colombian peasants to Washington insiders, observers say that the seven-year, $4.7-billion effort isn't working because aerial herbicide spraying and other eradication efforts have not been matched by sufficient efforts to encourage farmers to switch to legal crops.

"The coca eradication program has not achieved what we were promised," said Sen. Patrick Leahy (D-Vt), chairman of the Senate appropriations subcommittee on foreign aid. "The amount of cocaine reaching here is no less than it was five years ago."

Even the administration's own Office of National Drug Control Policy reports that cocaine purity on U.S. streets rose from 60 percent to more than 70 percent between July 2003 and October 2006, and that retail cocaine prices fell from more than $200 to under $140 per gram during the same time period.

In Colombia, cocaine cultivation has increased between 2000 and 2005. Even when eradication efforts work, most farmers simply replant coca nearby. "That means air spraying does not convince people," said Sandro Calvani, director of the U.N. Office of Drugs and Crime in Bogota. "You cannot change a dysfunctional social-economic situation by force alone."

In fact, Colombian farmers say that the spraying actually encourages them to plant more coca because it makes them more dependent on cocaine profits and also kills off food crops like plantains, cassava and sugar cane.

Colombia's government is now proposing to spend more anti-cocaine money on social programs than military operations, but the Bush administration is still calling for an eradication-focused strategy. With the new Democratic Congress, however, "Chances are there will be radical departures from what the Bush administration wants," said Adam Isacson of the Center for International Policy in Washington.