I define “open borders between the US and Canada” as meaning that US and Canadian citizens are free to enter the other country not just for short-term visits but for long-term visits and can settle in the other country to live, work, marry, or do other stuff, without needing to go through any immigration bureaucracy. Border checkpoints may still exist. One might define open borders more expansively to include all permanent residents of either country. As co-blogger John Lee noted in this post, the US-Canada border is not completely open in this sense: while citizens and even permanent residents can move freely between the countries for short-term visits, they still need to go through a bureaucratic (and uncertain) process in order to take up a job or settle long-term.

My two bleg questions:

• If the United States had a nationwide referendum among citizens (with simple nationwide vote-counting, unlike the complicated electoral college system used for presidential elections) on whether the US should have open borders with Canada, would the referendum pass, and by what margin? Feel free to provide probability distributions, and if necessary, indicate sensitivity to framing, timing, and contextual factors that affect the outcome. Note that “pass” here is based on a majority of those who vote, not based on a majority of the entire citizenry.
• If Canada had an equivalent nationwide referendum, would it pass? Again feel free to provide probability distributions, and if necessary, indicate sensitivity to framing, timing, and contextual factors that affect the outcome. Note that “pass” here is based on a majority of those who vote, not based on a majority of the entire citizenry.

UPDATE: A friend on Facebook had pointed me a while back to Annexation movements of Canada.