On Saturday Donald Trump sent a congratulatory tweet to new Prime Minister Scott Morrison:

This innocuous and pleasant message has generated howls of anger and disbelief from the north of the border along the lines of “hang on, stupid; the United States and Canada are greater friends than the United States and Australia!”

This got me thinking: sure, the Canucks like to think that they and the Yanks have got a special thing going, but isn’t there a lot of presumption and taking things for granted involved? There is more to being the best buddies than physical proximity (having been born in a...