Alberta will never join the United States. Those cowboys are smart enough to realize that trading a Federal government in Ottawa for a Federal government in Washington D.C. is a terrible idea.
"Alberta will never join the United States"
You keep missing the point - Alberta doesn't need to join the US for Canada to collapse,
If Alberta merely becomes an independent country, BC will have to break off from Canada, and if BC and Alberta form seperate country's then Quebec will leave, and then the so will the Maritimes.
But interestingly, there is NO WAY any Province, except Alberta, would even be considered for Application in the Union by the GOP Congress.
At best The Maritimes could hope for is acceptance as US Territories.