From the transcript, probably, Joe Rago who says this:
"or when Donald Trump says ... we can't build a wall on the Canadian border because is so much longer than the Mexican border ... in fact the Mexican border is longer than the Canadian border ..."
Well, Trump is right on this one:
Length of U.S.-Canada Land and and Water Boundary 5,525 miles (3987 miles without Alaska)
Length of U.S.-Mexico Land and Water Boundary 1,933.4 miles