SANTA MARTA, Colombia -- After flying over blackened coca fields, White House drug czar John Walters conceded that seizing cocaine, destroying coca crops and locking up drug traffickers in Colombia have had little impact on the flow of cocaine on American streets.
Walters nevertheless insisted that Washington must stay the course with so-called Plan Colombia, a $3.3 billion, five-year program mainly to train, equip and provide intelligence to Colombian forces spearheading the war on drugs.
"We have a history in the United States of not following through on programs like this," Walters said late Wednesday at an anti-narcotics police base near this coastal city after touring fumigated fields in the nearby mountains by helicopter.
During his three-day visit, Walters also met with President Alvaro Uribe and attended a funeral for nine police officers killed in apparent retaliation for a drug seizure.
The U.S.-funded Plan Colombia has led to a huge increase in drug seizures, with 48 tons of cocaine confiscated in Colombia last year compared to just 8 tons in 1999. Closer judicial cooperation between the two countries has allowed for 120 alleged drug traffickers to be extradited to the United States for trial in two years.
But aerial eradication, a key part of the aid package in which crop dusters fly over fields of coca -- the raw ingredient in cocaine -- and spray them with herbicides, has drawn sharp criticism, despite its success in reducing the area under cultivation.
The amount of cultivated coca crops across the country fell to 280,000 acres last year, from 420,000 acres in 2001 -- a 33 percent drop, officials say.
Peasants in the sprayed zones complain of health problems and rights groups say the herbicides kill banana and yucca plants. The U.S. and Colombian governments insist the spraying is safe and refuse to stop.
Still, Walters said Washington plans to re-examine the long-term fumigation strategy.
One concern is whether it's cost-effective. Colombia's counternarcotics police say 85 percent of sprayed crops are quickly replanted by farmers, meaning spray planes must repeatedly fly over the same zones.
Also, drug barons are quick to adapt.
Coca farmers have begun sowing in environmentally sensitive national parks, where the aircraft are prohibited from fumigating, covering the plants with protective chemicals or planting many small areas that are difficult to spot.
Another problem is security. Though they are escorted by helicopter gunships, the spray planes are hit by small arms fire about 26 times a month, according to a report from the U.S. General Accounting Office.
Last year, two planes last year were forced to land after being shot, and the State Department has since delayed seeking funds for new aircraft.
Walters said he believes fumigation remains important and effective, but that money could be used elsewhere.
"We need to make sure other areas are well-funded, such as interdiction," he said, referring to the use of radars and spy planes to track suspected drug smuggling flights. Nearly 30 planes have been forced down or destroyed on the ground by the Colombian air force this year.
Despite the progress here, cocaine prices on U.S. streets remain unchanged, a sign there is no shortage of the drug.
"Thus far we have not seen a change of availability in the United States," Walters said.
He contends drug traffickers still have tons of cocaine stored along transport routes and draw upon this stock to keep prices low.
The drug czar is confident that those stocks will start to run out if Colombian forces remain on the offensive.
In a speech to a dozen top anti-narcotics officials, Walters thanked them for their sacrifice. "You are making lives better for people who you will never meet," he said.