Nitpick (but that’s what we do here in the Dope): Reagan was actually the last president to expand US territory.† Understandable that the Economist would miss that factoid, since the expansion was small and flew under most people’s radar. Also, the previous expansion was under Wilson. Again, a very small expansion, but you gave credit for it to McKinley.
As far as Canadian response: someone (preferably a Canadian) should write a parody of American Woman titled American Fascist‡. That way you’ll have something to sing when the jackbooted American stormtroopers come goosestepping down your street.
† It’s unlikely Reagan had anything to do with this expansion other than to sign the enabling legislation and perhaps send congratulatory messages.
‡ Please be a bit more creative than just taking the original lyrics and substituting “fascist” for “woman”. Also, you lose points for getting an AI to do the writing.