Quebec was first colonized by France. Although it had been conquered by Great Britain in the French and Indian War, the vast majority of its residents were French-speaking Catholics at the time of American independence.

Britain enacted the Quebec Act of 1774 (note the year) to deal with the concerns of these residents. In particular, it guaranteed their right to adhere to the Catholic faith.

During the American Revolution, the Americans invaded Quebec in an attempt to bring the Quebeckers onto their side. However, they preferred to stay with the British.

After American independence, many English-speaking Loyalists moved to the Province of Quebec (which then included parts of today's Ontario) in order to stay within the British Empire.

At the time of American Independance (1776) both countries had imperialists (people who wanted to keep ties to Britain). America's War of Independance or Revolutionary War was a success which forced American Imperialists to leave America for Canada which at that time wasn't a country but a Dominion, similar to a colony. There were some actions in Canada at the time to try to leave the crown but not of significance. The inflow of these refugees only increased the populations support for the British Crown. I don't believe there was an American Appetite to invade either through invitation or conquest.
Canada didn't become a country until after America's Civil War and largely because of the threat of American invasion. America's 19th Century History was largely influenced by the push to control the continent under the idea called Manifest Destiny. It was this pressure that created Canada as a country although it lacked complete soveriengty until after World War One. In 20th Century Canada we've seen some regional talk of leaving Canada and joining the United States by those regions who felt underserved. The Maritime provinces of New Brunswick, PEI, and Nova Scotia are economically depressed and culturally similar to the state of Maine and there's been some minority discussion of creating a union there. Problems there include addressing New Brunswick officical bilingualism which no other state would be willinng to take on due to cost. The western Prairie provinces of Alberta and Saskatchewan have also been underserved by the Federal government by Ottawa's National Energy policy in the '80s and Alberta is certainly the province with the second most seperatists after Quebec (who would have no interest in joining America). Quebec's seperation referendum of '96 made other provinces also consider the idea behind closed doors. TL;DR: there isn't popular support for it in Canada Source: Canadian Social Studies Teacher

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