This is very useful history....

[Most of us know something of the antagonisms which erupted during the last quarter of the 20th century between French-speaking and English-speaking citizens in Canada. These antagonisms grew out of excessive consolidation of the Dominion, arraying the nine provinces of Anglo-Canada against Quebec as the geopolitical bulwark of French Canada. There was a clash of two civilizations not unlike that which occurred in the United States between the North and the South. The result was a powerful separatist movement in Quebec which repeatedly elected governments, and offered two referendums on independence, in the second of which the vote for secession from the Union very nearly carried.

The question then arose whether the Constitution of Canada permits secession of a province from the Confederation. Under the organic statutes, there is no express right or formal mechanism for secession. But Canada is blessed by the customs and conventions of the British Constitution which were conveyed to the Dominion by the preamble of the British North America Act of 1867, including the principle of the Glorious Revolution on which the Crown rests: in extraordinary circumstances, the constitutional right of the people to free, peaceable, and orderly reformation of the government, even if contrary to the usual forms of fundamental law, might take the form of secession from the Union. Accordingly, in the Reference on certain Questions concerning the Secession of Quebec from Canada, [1998] 2 S. C. R. 217, the Queen’s judges advised that the people of Quebec enjoy a constitutional right to aspire for independence, and a constitutional right to a free and peaceable referendum on independence at public expense whenever their elected government determines; that, if in such a referendum the people of Quebec vote in the affirmative by clear majority on a clear proposition for independence, the government of Canada will have a constitutional duty to negotiate terms of separation, nor may the government of Canada in such a situation threaten or use force of arms to resist secession; and that, if negotiations fail, and the government of Quebec then unilaterally proceeds to independence recognized by other nations of the earth, a new constitutional order will thereupon be established.

The consequences of this judgment have been remarkable: the antagonisms between Anglo-Canada and Quebec have essentially evaporated. The people of Quebec reacted to the concession of their rights within the Union by electing a federalist government. The Union now waxes strong. And Canada is loyal to the Crown from sea to sea. It might first appear that the right of secession will bring anarchy to a federal Union. Yet by operation of moral causes, the right of secession, which is the essence of Southern Constitutionalism, has exactly the reverse effect. In commenting upon the Union of Southern States established in 1861, Lord Acton explained why: “When the Confederacy was established on the right of secession, the recognition of that right implied that there should never be occasion for its exercise. To say that particular contingencies shall justify separation is the same thing as to say that the Confederate government is bound within certain limits, under certain conditions, and under certain laws. It is a distinct repudiation of the doctrine that the minority can enforce no rights, and the majority can commit no wrong. It is like passing from the dominion of an able despot to a constitutional kingdom.”]