When setting a scene in the future, there are plenty of ways to imply that the present has been left behind without dilating doors or specific calendar references. Altering the political landscape is one sure-fire way to do this, and it's not uncommon in science fiction. Thirty years ago, for example, a writer could have gotten a great deal of mileage from a simple, offhand reference to the Soviet Union no longer existing.
The United States itself tends to be the target of this alteration more often than not, but Canada likewise ends up being rewritten fairly frequently - no surprise, given the sheer number of North American writers in the science fiction field. Occasionally, possibly as a projection of Canada's apparent "instability" in the wake of the 1995 Quebec referendum, it's broken up into multiple countries - Transhuman Space uses this to help establish its world of 2100, where "Canada" has been reduced to Ontario, Manitoba, and Saskatchewan, and Pravda Online discussed it in the context of "the ever aggressive Rump USA/Canadian police state" last year - because if there's anyone who knows anything about police states, it's Russians.
More frequently, though, the future is partially defined by Canada having become part of the United States of America. While annexation hasn't been an aim of the American government since the nineteenth century, and Canada's historically fought for its life against the prospect, when it comes down to individual authors perspectives are frequently different. From tabletop games like Shadowrun to video games like the Fallout series, where resource motivations led to the conquest of Canada by the US in the mid-21st century, and Mass Effect - its Cerberus Daily News updates make reference to a "United North American States" - and literature like David Foster Wallace's Infinite Jest and E.E. "Doc" Smith's Lensman series, there seems to be a small but definite number of creators who think that the idea of annexation still has some traction in the twenty-first century and beyond.
It's even passed into the realm of the real - witness the North American Union, and the inexplicable fear some Americans seem to have of the prospect. Witness Stop the North American Union, a rather... emotionally charged take on the subject. From my perspective, Americans reacting like this to the idea of the NAU is laughable for one key reason - in any political unification, the United States would have the upper hand. It outweighs Canada and Mexico by itself. But, for some reason, it doesn't seem like they ever stop to consider that maybe the rest of North America is not too eager to surrender its sovereignty to Washington.
For myself, I feel - particularly given that today is Canada Day - that the annexationists are entirely wrong.
The fact is, Canada and the United States aren't just the same shit with different names. Two hundred and twenty-five years of independent development, while progressing in the same general direction, has seen the two countries chart divergent courses. In my experience, the basic cultural similarities that Canada and the United States share only serve to highlight the differences in greater relief. The time for Canada to become part of the United States ended in the nineteenth century.
Nevertheless, I don't think that will stop this trend. I find it plausible that in the near future, we may see an uptick in the number of movies, television shows, stories and games that include Canada joining the United States as a sort of wish-fulfillment exercise - defining the future in part by positing a United States that's moved so far beyond the image of a sole, unchecked superpower invading countries left and right that other countries are kicking down their door to be united under the Constitution. All it ignores is the age-old truth that not everyone wants to be an American.
Happy Canada Day, and may there be many more.