It's a border, deal with it. There are still some very impressive cannon set up in Ft. Niagara, Youngstown, NY, aimed at Canada. Remember the Battle of Ridgeway (charge of the Fenians)? Good defenses make good neighbors...War plan red was not actually a plan to invade Canada, it was a plan to respond to an attack by the British Empire which was not at all expected.
Also it has been declassified since 1974. I've known about it for ages.
Only Plan Orange [vs Japan] was taken seriously.