I did see clips of Rick Mercer talking to Americans, and yes, he did reveal quite a bit of American ignorance about Canada (haha, President Jean Poutine..... that's funny!). I do agree, in fact, that Americans tend to be ignorant about the rest of the world. I have heard many jokes about American ignorance about Canada.
But here's my main point: if Americans did pay more attention to the rest of the world, do you really think Canada would be among the highest priority among the world's countries?
Here's my story relevant to the topic, as well as my many observations:
I was born and raised in Northern California to parents from the Philippines. I always knew that Canada was more than a northern "wilderness," French speakers, and Mounties (in fact, as a kid, I thought of Canada as like the US, but having guarded more aspects of its British heritage that Americans tossed).
But Canada didn't really enter my radar until my dad's brother migrated with his family to Vancouver when I was 11. Because his sons were my age, I had a good reason to go there nearly every summer. My frequent visits made me fall in love with Vancouver, and I kept coming back, even when I didn't feel as close to my cousins as I used to. I also became curious about the rest of Canada, and got to see much more of it as an adult. I like the majority of what I have seen. I even intend to live there after a few years of going to other countries.
What if, however, my uncle didn't migrate to Canada? Or what if he migrated to a part of Canada that my teenage self would not have appreciated so much. I don't think Canada would be so high on my radar. Would I be ignorant of the world outside the USA, though? Here are some main points:
1) As my parents are from the Philippines, that country would, one way or another, be on my radar. With or without Canada in my life, the Philippines would always be on my radar. And I think many people of recent immigrant background (self, parents, or grandparents) can say the same. For many people of recent immigrant background in the US (like anywhere else), their world will often revolve largely around both the "old country" and the "new country" (in my case, Philippines and USA). Additionally, many of us will have friends whose recent origins are from countries other than these, and those countries will be on our radar as well (for example, I have many Chinese friends, so China and its neighbours are on my radar as well).
So since most immigrants to the US from previous generations are from Europe, while most immigrants since 1965 are from Latin America and Asia, I think it's not hard to find people in the US who place countries from those regions high on their radar.
2) I have white American friends who have been in the States for generations, and have few friends of recent immigrant background (besides me, of course), but they do take huge interest in the pop cultures from countries such as the UK, Germany, and Japan. As long as the US has been a major world power, its closest rivals have generally been in Europe and Asia, so aside from the influence of immigrants from those regions, continued exposure to the pop cultures of those regions could put their countries further in the minds of many Americans. Good example: Japanese Anime
On that note, I actually enjoy and appreciate CBC programming and many bands from Canada - but I noticed that even many Canadians don't seem to, because they prefer that which comes from the States. So if many Canadians don't seem to have Canada on their radar, how can anyone else?
3) When you talk about border issues, Canada's only concern is the US. The US, on the other hand, is concerned not only with Canada, but with Mexico and other countries to the south. And whatever issues concerning smuggling of drugs, weapons, and people may happen at the Canada/USA border, I guarantee you it's easily 100 times bigger at the USA/Mexico border. I mean, to my knowledge, the USA/Mexico border receives 10,000 illegal crossings into the USA DAILY!!!! I don't think the Canada/USA border can even come close! And particularly being from California, we get a plurality of it. Mexico is thousands of times visible in the daily live of a Californian than Canada would ever be!
On that note, that's why there are more Mexicans in the US than there are total people in Canada. Whereas whatever Canadians migrate to the US tend to blend in too well.... even better than out-of-state Americans from some places would. In California, someone from Texas or Tennessee would stick out more likely than someone from Toronto would. (Likewise, when I go to Canada aside from Quebec and parts of Atlantic Canada, I don't get noticed as an outsider, whereas I would in many US states).
And if the Canadian who moved to the US is of an "ethnic" background, they will be more likely to identify with locals if their ethnic background than with being Canadian. For example, a Chinese-Canadian from Vancouver who moves to California will likely identify much more easily with Chinese locals in California than they would with a white Quebecois or Newfoundlander who also moves to California. So my point with this point is that if we have millions of Mexicans everywhere who make their presence largely visible, whereas Canadians often blend in better than out-of-state Americans do, that takes away some pressure to pay more attention to Canada.
Additionally, while 90% of Canadians live within 150 km of the US border, a smaller percentage of Americans live within the same distance of the Canadian border. In fact, even more live the same distance from the Mexican border, and like I said, that includes many Mexicans themselves.