For nearly eight years, Calgarian John Wrenshall victimized boys as young as four, and hosted pedophiles at his brothel in Thailand. Last month, he was sentenced to 25 years in prison after pleading guilty to three counts related to these offences.

As horrifying as the Canadian’s crimes were, Wrenshall’s trial went down in a New Jersey courtroom. He was pursued and prosecuted by the American justice system. While Canada has its own sex tourism law on the books, enforcing it has been a low priority.

“Children represent what is best in us,” said U.S. Attorney Paul Fishman in his closing arguments of the Wrenshall sentencing. “Wrenshall’s monstrous conduct represents the worst.”

There was a time 15 years ago when I was impressed by how quickly the Canadian government took a sentiment like Fishman’s and moved on addressing this horrific issue.

At 13, I’d just returned from a revealing trip across South Asia where I’d witnessed the impact of sex tourism on underage girls and boys. In a meeting with then-Foreign Affairs Minister Lloyd Axworthy, I presented him legislation from Australia, Germany and France that allowed for the prosecution of citizens, like Wrenshall, who travel abroad to abuse kids.

Axworthy took the matter to Justice Minister Allan Rock. Almost as quickly as my mentor Alan and I found pimps handing out “menus” of young children to foreigners in seedy, Bangkok markets, the Canadian Criminal Code was amended to include an extraterritorial child sex offender law.

I was filled with hope following this triumph. Today, it seems futile.

Wrenshall, who previously served 10 years for assaulting Canadian children, was indicted by the U.S. government only because some of his clients were American. Meanwhile, between 1993 and 2008, the Department of Foreign Affairs provided consular assistance (for example, ensuring equitable treatment in jail and notifying next-of-kin) to over 150 men charged with child molestation in foreign nations. Only three people have been convicted under Canada’s sex tourism law.

Compared to other nations, Canada has taken few measures outside of Parliament to prevent or prosecute tourists who travel internationally to exploit children.

Australia has a national tip line that citizens can call if they witness suspicious activity. The United States buys billboards warning nationals of 30-year prison sentences if they are caught abusing children. Both countries have officers stationed in Southeast Asian nations to help local police capture sex tourists. These measures helped Australia convict 19 people between 1995 and 2007, while the United States saw 47 convictions since 2003, according to a recent study by the University of British Columbia.

The United States and Interpol have also taken measures towards prevention. They notify destination countries if a convicted pedophile (like Wrenshall) wants to visit, allowing local authorities to decide if they want to admit them.

These measures, while not foolproof, attempt deterrence where virtually none exists.

Years ago, I witnessed a sting operation in an outdoor seating area of a Philippines McDonalds. Two men sold two underage girls like hamburgers in the restaurant. They were frightened, but it was clear the girls had sat in front of other tourists before. After the police made the arrests and they were brought to a rehabilitation centre, it was clear they would spend years working to overcome the emotional and physical wounds that accompany this horrific practice.

Meanwhile, their pimps received the kind of slap-on-the-wrist sentences that help this lucrative industry grow.

Increased foreign travel and the Internet have only made it easier for pimps to connect with potential abusers. Sex tourism is now a multi-billion dollar industry that, according to UNICEF, exploits about two million children each year.

The RCMP has told The Star that it prefers suspects be tried in the country they were accused in, so that other governments don’t shirk their responsibilities. In saying this, we’re shirking our own. Not only are sex tourists exploiting children, they are also exploiting the systems of struggling nations dependant on tourism dollars.

Fifteen years ago, I was astounded by how quickly the government could move to create a law with the power to protect children. Now, we need to start using it.

Marc and Craig Kielburger are children's rights activists and co-founded Free The Children, which is active in the developing world. Their column appears Mondays online at thestar.com/globalvoices.