Easier to just deport the people who ‘interfere’ in US elections.
If they come back, then it’s on Canada to stop entry or we close the entire border with Canada.......
Keep in mind that something like 75% of the Canadian populace lives within 150 miles of the US border, and 25% or more work in the US. Financially, it would be devastating.
Five years hard labor down at Gitmo, then deported with prejudice.