Although prohibition has manifestly failed to stem the use of narcotics, it has generated enormous costs and led to perverse outcomes. In the United States, the war on drugs is producing alarming violations of civil liberties, weakening the rule of law, and compromising law-enforcement efforts. Such unintended consequences, however, extend well beyond the U.S. borders. At a Cato Institute Conference held in November, international leaders and prominent scholars from around the world came together to review the global impact of drug prohibition and introduce practical alternatives.

In his opening address, Jorge Castañeda, former minister of foreign affairs in Mexico, looked at the initiation of the war on drugs in his country. “The war was declared on false premises,” he said — adding that fears of increased violence and rising consumption were overblown. Prohibition has done little to reverse these missteps, he noted. “If the premises were false then, they’re still false now,” Castañeda declared, concluding that Mexico “should make advocacy of legalization in the U.S. its main task in foreign policy.”

Tim Lynch, director of Cato’s Project on Criminal Justice, gave a “brief tour” of the U.S. system of law, focusing in particular on the ways in which the drug war has eroded America’s bedrock legal principles. At the same time, he acknowledged the “palpable sense that the momentum has shifted” from the warriors to the reformers — due, in part, to what he calls “drug war exhaustion.”

Luis Alberto Lacalle Pou, Speaker of the House of Deputies in Uruguay, and Romesh Bhattacharji, former narcotics commissioner of India, explained how the hemispheric battle has played out in various regions of the world, including Uruguay, Pakistan, and Afghanistan. Enrique Gómez Hurtado, former senator in Colombia, reflected on the 1995 assassination of his brother, political leader Alvaro Gómez Hurtado, at the hand of drug traffickers.

This tragedy, he said, has given him “a deeper understanding of how traffickers operate in the political arena” and the futile efforts to stop them. “We press on,” he said, “but are making no ground.”

Other speakers at the conference included Fernando Henrique Cardoso, former president of Brazil; Peter Hakim, president emeritus of the Inter-American Dialogue; and columnist Glenn Greenwald, who followed up on his 2008 Cato study, “Drug Decriminalization in Portugal.” Former secretary of state George Shultz and former Mexican president Vicente Fox addressed the conference in pre-taped videos. Ethan Nadelmann, executive director of the Drug Policy Alliance, discussed his attempts to “reduce the role of criminalization in drug control.” The most optimistic sign of progress, he noted, is “the transformation of public opinion towards marijuana.”

According to Gallup, the number of people in favor of legalization increased from 16 percent in 1970 to 50 percent last October — the highest number recorded to date. Ordinary citizens are thinking about these issues as never before. And they’re not the only ones. By the time the conference had ended, the White House’s Office of National Drug Control Policy had responded with more than a dozen messages on Twitter. The war on drugs marches on. But the debate, at the very least, certainly seems to be resonating.