Tariffs aside, considering Canada is our neighbor and has roughly 68k active military personnel vs 1.28 million in US, it should most definitely align itself with US on national security grounds. I believe that if Canada was ever under threat from another state, that US would definitely step in to help. Also, this is apples-to-apples comparison because the total land area (to be protected) covered by each state is approx. equal (6 million square miles or 9.8 million square kilometers).