..Canadian border official..

[GSCole]

As stated in my original post, it was a Canadian border checkpoint
official.  Perhaps the addition of a hyphen would clarify the statement,
i.e., Canadian-border checkpoint official.

Not a misremembering, but a statement of a conversation.  The speaker
who related the incident to me called it the Canadian border, but he was
not a geographer, nor was he a historian with regrets about the outcome
of certain military events in 1812.

I don't know if the official questioning begins at the border or exact
crossing point, or begins before you actually enter the country, or
after.  My experience is that the questioning takes place several
vehicle lengths before the actual checkpoint is reached.  If the
questioning actually occurs prior to entering U.S. space, the official's
response (Where do you think you are now?) works.  Otherwise, we might
have an official who is attempting to make a dumb joke.

I'm not familiar with the border defining conventions of the U.S. and
Canada.  When attempting to leave Canada, traveling to the U.S., if I'm
refused entry to the U.S., am I in Canada when the refusal is issued, or
in the U.S.?

George Cole
Shippensburg University