Christine Sismondo’s Canadian Moments column looks at what history can teach us about a current moment in Canadian news, politics, or culture. Read more of her columns here.

As Canada hurtles towards the date that weed is legalized federally on Oct. 17, there remain a lot of unanswered questions amid a fraught patchwork of laws and regulations that depend on your province, your city, even your condo. Big change like this often is awkward, and laws have to catch up.

But it’s also raised serious questions about how legal weed will play out at the United States border. Obviously, bringing any weed into the U.S.—even small amounts for personal use—is just as illegal as ever. But recent reports have suggested that U.S. border services might also deny entry to Canadians who tell them they’ve ever consumed marijuana, worked in the Canadian marijuana industry, or even have investments in pot stocks. Perhaps the most alarming scenario involved border agents checking Canadians’ credit card data—accessible to them if it’s stored on an American server—to check if the prospective border-crosser ever bought pot with plastic.

If these policies feel archaic and draconian, straddling the fine line between absurdity and inexcusably intrusive in how it would affect everyday Canadians’ ability to cross the border for family or work, your instincts are right. After all, they have plenty of echoes of the last time Americans have worried that Canada posed a threat to the moral health of the people of the United States, resulting in tensions at the border. During Prohibition from 1920 to 1933, key anti-alcohol forces in the U.S. devoted considerable energy into pressuring Canada to change its drug policy, even often overstepping its jurisdiction, all for the sake of preserving American morality.

For 25 years, the Anti-Saloon League (ASL), the American anti-alcohol group, took aim at a most ambitious goal: changing the U.S. Constitution. It sought to ban the manufacturing, transport, and sale of intoxicating liquors—and in 1919, Congress officially passed the 18th Amendment, doing just that.

It was a crowning achievement for an organization that had successfully transformed a women-led grassroots temperance movement into a powerful, well-financed lobby group that effectively invented “pressure politics.” And riding the high of accomplishing this seemingly impossible feat, the ASL turned its sights to global domination, immediately establishing the World League Against Alcoholism (WLAA), a group designed to pressure the rest of the world to follow America’s example. First stop? Canada.

At that point, Canada was already mostly dry itself, owing to the War Measures Act, which had suspended some normal rights including drinking. But unlike the U.S., Canada had no hard-and-fast, permanent federal law around alcohol, so provinces were free to settle their own fate after the Armistice, and Quebec’s “prohibition” was the first to be called off in 1919.

The ASL’s argument was that there were serious practical border issues around this, from smuggling to Americans being tempted to take a quick weekend trip to Montreal for an alco-holiday. As the prolific and militant ASL activist Ernest Cherrington wrote in his 1922 book, America and the World Alcohol Problem: “The boundary line between Canada and the United States extends for 3,898 miles … The single province of Quebec, Canada, on our northeastern border, imported, during the fiscal year 1921, more Scotch whisky than had been imported into that province during the entire 10 years proceeding.” That whisky, he argued, wasn’t for Quebecers’ personal use, but was just passing through on its way to southern Ontario, where he claimed that 1,000 cases of contraband liquors were smuggled across to Michigan every 24 hours.

Cherrington used this shocking (and frankly, suspicious) argument to justify the location for the WLAA’s 1922 convention—Toronto. In November 1922, the WLAA held a five-day event that the Toronto Star dubbed a “monster temperance convention,” thanks to the many foreign and local dignitaries in attendance—delegates from 20 countries, including Japan, Peru and Finland, as well as Toronto Mayor Alfred Maguire, Ontario Lieutenant Governor Harry Cockshutt and, of course, Cherrington himself. There were keynote speeches, banquets at the King Edward Hotel, public health seminars, and prayers, plus a seminar by a lawyer on the “Ways and Means of Securing Action Through Government Officials for the Enforcement of Law”—a crash course, effectively, in how to pressure local police and city politicians into making more arrests.

But the convention didn’t work. Instead, by 1925—just three years after the WLAA event—Ontarians were quaffing back Fergie’s Foam (4.4 per cent beer made legal by Premier Howard Ferguson) and, two years after that, witnessed the introduction of retail liquor stores, leaving only two dry provinces (P.E.I and Nova Scotia). The tables had turned on Prohibition and the ideas that fuelled it in Canada; one political poster framed it as a victory for progressives, who had seen the “falseness and dishonesty” of Prohibition, which had been built on a “foundation of bigotry and intolerance.”

That aspect of Prohibition—that it was a pretext to increase surveillance and incarceration of minorities—wasn’t just dawning on Canadians. Every violent day in the United States made it clearer that bigotry was built into the booze ban. Consumption was legal in private homes and the rich could afford to pay fines when caught in public, while minorities who couldn’t afford the fines were being jailed. In places with uneven enforcement, the Ku Klux Klan’s night riders even took it upon themselves to raid speakeasies and burn crosses on the lawns of Italians and Jews who were suspected of being bootleggers.

But despite the chaos and the increased social-justice arguments against Prohibition, U.S. President Herbert Hoover’s administration refused to back down. Instead, he increased penalties at home, putting pressure on foreign governments to cooperate and encouraging more aggressive law enforcement.

These U.S. edicts led to regular skirmishes on the Great Lakes and in border towns in Quebec and the Prairie provinces, as Americans chased smugglers into Canadian territory where they had no jurisdiction. And tensions between the two countries on the issue continued to climb, with relations already a little tense for most of the 1920s, thanks to spats over immigration and trade. But then, in 1929, one such conflagration led to the sinking of the I’m Alone—a Canadian rum-running vessel in the Gulf of Mexico, some 200 miles outside of American waters, killing Canadian boatswain Leon Mainguy. Although the diplomatic correspondence was “moderate and friendly,” according to a front-page article in The Globe, Canadian authorities, in consultation with the British, were debating whether or not the sinking was authorized by the U.S. government—which would have made it an act of war—or simply a case of Coast Guard agents gone rogue. Ultimately, it decided, despite Canadian resentment, to arbitrate, and the issue was finally settled six years later.

Americans didn’t just go beyond their jurisdiction in international waters. The U.S. Bureau of Prohibition sought to station its agents on Canadian soil so that they could gather intelligence about departing shipments and alert colleagues on the other side of the Great Lakes that a boatload of booze was headed their way. On this, however, Canadian authorities said yes. This was followed up by reports of gunplay on the Canadian side of the Detroit River, as the Coast Guard opened fire—at least once with machine guns—on two separate suspected rum-runners. The city council in La Salle, Ont., condemned the American officers for excessive force, pointing out that in Canada, “good … officers catch rum-runners without firearms.” And one parliamentary session in the House of Commons in 1930 saw members demanding an accounting of the number of ships destroyed and Canadian citizens “murdered” by U.S. agents—a debate that made the American news, too. People were horrified about excessive force and the fact that this American drug war was being exported to Canada—but it also became a question of Canadian sovereignty.

The irony of the manoeuvres in Canada is that, despite the presence of rum-runners, most of the liquor Americans drank didn’t come from here. In the beginning, far more would have come from the United Kingdom and France, via St. Pierre and Miquelon. When that slowed down, American ingenuity took over, and bootleggers started making counterfeit spirits from industrial alcohol, which almost certainly wound up with a bigger market share than genuine contraband liquor. The same, of course, is true with weed: As Eric Schlosser uncovered in his 2003 book Reefer Madness, more weed is grown domestically in America than is smuggled in from Canada, Mexico, or anywhere else.

As we anticipate a seemingly parallel drug policy chasm looming around marijuana, the Prohibition episode is instructive: It’s possible that, in time, reason will prevail in the U.S. on the issue of marijuana. After all, recreational use is already legal in nine states, and people like Cynthia Nixon, who was defeated this summer by Governor Mario Cuomo in New York state’s Democratic primary, are openly calling decriminalization a racial-justice issue, bringing the underlying logic of drug laws out into open discourse.

But while we wait, we should steel ourselves for more tensions at the border. It’s not just a matter of history repeating: once we understand that drug laws are at least as much about providing a pretext for stop-and-search as they are about actually stopping the trafficking of drugs that are, after all, grown in mass quantities on both sides of the border, it’s hard not to expect them to be used in full force now. That’s especially true since the border is already a hot-button issue in trade, security and immigration debates.

And the Prohibition episode offers a warning, too: that anti-drug advocates, in their zealotry, seem to have about the same amount of respect for sovereign countries’ drug policy choices as they do for the civil rights of their own citizens.

Which is to say, remarkably little.

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