§ 338 lets the President place tariffs on countries who impose “any unreasonable charge, exaction, regulation, or limitation which is not equally enforced upon the like articles of every foreign country” or “in fact against the commerce of the United States, directly or indirectly, by law or administrative regulation or practice” [1].

Just from the text, these powers appear quite broad.

[1] https://www.law.cornell.edu/uscode/text/19/1338#:~:text=Prio... §338 of the Act was apparently codified as § 1388

Yeah, I'm on Canada's side of the conflict, but there's really no question as a matter of US law that the alcohol restrictions are sufficient to satisfy the preconditions for this.