The United States’ war on drugs has failed and will continue to do so as long as it emphasizes law enforcement and neglects the problem of consumption, a Washington think tank says in a report co-chaired by a former president of Mexico.

The former president, Ernesto Zedillo, in an interview, called for a major rethinking of U.S. policy, which he said has been “asymmetrical” in demanding that countries such as Mexico stanch the flow of drugs northward, without successful efforts to stop the flow of guns south. In addition to disrupting drug-smuggling routes, eradicating crops and prosecuting dealers, the U.S. must confront the public health issue that large-scale consumption poses, he said.

“If we insist only on a strategy of the criminal pursuit of those who traffic in drugs,” Zedillo said, “the problem will never be resolved.”

The indictment of Washington’s counter-narcotics campaign comes in a report released this week by the Brookings Institution that advocates closer engagement with Latin America and the Caribbean. U.S. influence in the region has slipped dramatically during the eight years of the Bush administration, and the report suggests an incoming Democratic government led by Barack Obama can open opportunities for better ties and communication.

Among its recommendations, the report urges a fresh approach to Cuba, including loosening the long-standing U.S. embargo, overhauling immigration policies, and enhancing “hemispheric integration” on the economic and energy fronts.

The report, which is the work of Brookings’ Partnership for the Americas Commission, offers especially pointed criticism of the way the drug war has been waged.

Contrary to government claims, the use of heroin and cocaine in the U.S. has not declined significantly, the report says, and the use of methamphetamine is spreading. Falling street prices suggest that the supply of narcotics has not declined noticeably, and U.S. prevention and treatment programs are woefully underfunded, the study says.

“Current U.S. counter- narcotics policies are failing by most objective standards,” the report says. “The only long-run solution to the problem of illegal narcotics is to reduce the demand for drugs in the major consuming countries, including the United States.”

Zedillo cited skyrocketing violence in his own country as an example of the damage done by these policies. More than 4,000 people have been killed in Mexico this year in drug-related warfare between government troops and traffickers, and among rival drug gangs. Many of the weapons confiscated in raids and shootouts came from the U.S.

Zedillo, who served as Mexican president from 1994 to 2000, spoke by telephone from Yale University, where he is an economics professor and director of the school’s Center for the Study of Globalization. He is co-chairman of the Partnership for the Americas Commission with Thomas R. Pickering, a former U.S. undersecretary of State.

Where the U.S. has had success, as in the reduction of coca production in some areas of Colombia, the gains are not sustainable, Zedillo said, because cultivation merely moves to other zones.

“And that way, the fight goes nowhere,” he said.

The report urges the U.S. to take responsibility for stemming the transport of an estimated 2,000 guns a day across the border; to expand drug prevention programs in schools and redirect anti-drug messages to younger people by emphasizing cosmetic damage as well as health risks; and to greatly enhance drug courts, a system that incorporates treatment into prosecution.

John P. Walters, head of the White House Office of National Drug Control Policy, recently defended U.S. efforts. In Mexico to discuss a pending anti-drug aid package, Walters said a decline in positive drug tests at American workplaces indicated consumption was down, and he said authorities were taking steps to curtail gun shipments.

But a report this month from the U.S. Government Accountability Office, commissioned by Sen. Joe Biden (D-Del.), now the vice president-elect, said the government’s most ambitious counter-narcotics program, the $5-billion Plan Colombia, failed to meet several goals. Interdiction halved opium and heroin production in Colombia from 2000 to 2006, but coca and cocaine production continued to grow, it said.

Wilkinson is a Times staff writer.

wilkinson@latimes.com