The Canadians must have learned from the U.S. War to Prevent Southern Secession (a.k.a. the "Civil War"). Even the Soviet Union was enlightened enough to legally permit secession. The U.S. Constitution does, as well, under the 10th Amendment, as one of the rights retained by the states, but U.S. President Lincoln and U.S. courts haven't recognized this right.
Discussion
Lincoln was a tyrant, total slime