It’s remarkable how long Americans had designs on annexing Canada to the United States. Theodore Roosevelt wrote in 1887 that it was a shame that the US hadn’t “insisted even more than we did upon the extension northward of our boundaries.” It would have been better for “Columbia, Saskatchewan and Manitoba” if they had been part of the US, since they would “hold positions incomparably more important, grander, and more dignified than they can ever hope to reach either as independent communities or as provincial dependencies of a foreign power.” With a tinge of regret, TR admitted it was too late: “we want no unwilling citizens to enter our Union; the time to have taken the lands was before the settlers came into them.”

A couple of decades earlier (1864), the editorial of the New York Herald was bolder: “four hundred thousand thoroughly disciplined troops will ask no better occupation than to destroy the last vestiges of British rule on the American continent and annex Canada to the United States.” One would have thought that a civil war provided sufficient occupation for all available troops.