In the long view it is probably better if Canada and the US don’t burden each other with a formal economic agreement. Canada is getting some degree of American immigration already. If the USA continues to fail its people there will be a much larger emigration to Canada.

It is the vast consumer base that gives the USA such clout in any trade relationship. Prime Minister Trudeau and his cabinet and legislators should prepare to have a larger population and far more economic clout than before. Americans have good work ethics. Canada will find their immigrants of value.