I don't suppose anybody ever caught that episode of The Hour where George was talking with a man who's ancestor was one of the generals of the forces from the US (Militia) who invaded Canada at that time?
From what he was told down the family lines, the mentality of the US at that time was that the people in Canada didn't want to be part of the British Empire, that they would be liberating us, and that we'd be welcoming them with open arms because we genuinely wanted to be Americans too, etc. (Sound Familiar?)
5:45 into the Video he starts the explination. (Just Scroll to Jump to the Time)
I liked the part where the New York Militia walked away because they had no beef with Canada... cudos NY.