I think you may have fallen into the trap thinkint that this is a rational action with a clear goal.

I mentioned in the previous post that Canada is willing to spend extra resources to avoid a trade war.

That means nothing to trump and this administration, you are trying to use logic to justify decisions made out of personal ego.

Edit: also wanted to add that more guns, drugs and people illegal flow into Canada from the US than visa versa.

Maybe the US should consider securing their own borders