Prime Minister Stephen Harper made what some thought was a surprising admission at the Summit of the Americas in Cartagena, Colombia, when he told reporters that existing strategies to combat the drug trade are "not working."

But Harper wasn’t willing to embrace legalization, either, saying April 16 in Santiago, Chile that, "all leaders are interested in looking at a variety of approaches but very, very few leaders think that anything should be done other than fighting this particular scourge on our populations."

While the week began with Harper’s commitment to continue battling drugs through enforcement, it ends with two other notable developments in the drug debate.

The first is a bid by activists in the Netherlands to stop a government plan to bar foreigners from purchasing pot in the country's renowned marijiuana coffee shops, and the other is 4/20, a public celebration of pot use that takes place every April 20 and has become a de facto political statement in favour of drug legalization.

The history of 4/20 is somewhat hazy, but it is widely thought to be the work of a group of teenagers who in 1971 made a pact to find an abandoned cannabis crop near their homes in San Rafael, Calif., and designating 4:20 p.m. as their meeting time. The number has since taken on a mythical quality, inspiring pot enthusiasts to stage an annual day of celebratory cannabis consumption.

With 4/20 revelers expected to hold smoke-filled demonstrations across the country and around the globe, here’s a round-up of what world leaders and media commentators have said about the drug legalization issue in recent days.

"I think what everybody believes and agrees with, and to be frank myself, is that the current approach [to the drug trade] is not working, but it is not clear what we should do."

-- Canadian Prime Minister Stephen Harper at the Summit of the Americas

"My administration’s position… is that legalization is not the answer."

-- U.S. President Barack Obama at the Summit of the Americas

"It's hardly surprising that Mr. Obama is taking this line, but it's still a major bummer. The claim that it is drug tolerance, rather than the ‘war on drugs’ itself, that is the greater threat to the rule of law and to public health in the world today is bogus."

-- April 16 editorial in The Economist

"Over the past three decades, we have reduced illegal drug use in America. Over the long term, rates of drug use among young people today are far lower than they were 30 years ago."

-- R. Gil Kerlikowske, director of the White House Office of National Drug Control Policy, in an April 18 editorial for the Huffington Post

"Drug policy is routinely presented as a choice between the war on drugs and corner stores selling heroin to kids. That’s nonsense. There is a vast array of regulatory options between these two extremes. We need to lay them out." 

-- Columnist Dan Gardner writing April 18 in the Ottawa Citizen 

"We cannot eradicate global drug markets, but we can certainly regulate them as we have done with alcohol and tobacco markets. Drug abuse, alcoholism and tobacco should be treated as public health problems, not criminal justice issues."

-- Guatemalan President Otto Perez Molina, writing April 7 in Britain’s The Guardian newspaper

"While alcohol … continues to wreak havoc in America, supported by a $6 billion-a-year alcohol industry advertising campaign extolling the joy of inebriation, the far less harmful drug of marijuana remains illegal and continues to ruin people’s lives — only if they are caught possessing and convicted of that crime."

-- Lawrence O’Donnell in an April 17 monologue on MSNBC’s The Last Word with Lawrence O’Donnell

"One side can be all the consumers go to jail. On the other extreme is legalization. On the middle ground, we may have more practical policies." 

-- Colombian President Juan Manuel Santos at the Summit of the Americas

"I want to say this just as clearly and as forthrightly as I can, marijuana prohibition, criminal prohibition of marijuana, is a complete failure."

-- Former U.S. district attorney John McKay, who prosecuted B.C. marijuana activist Marc Emery, speaking at a lecture in Vancouver on April 18

"There is no reason to think today’s levels of [drug] addiction are anywhere near the levels that would be reached under legalization."

-- Journalist George Will in an April 5 commentary in the Washington Post