the joke I heard growing up is they'd ask suspected spies to sing the Star Spangled Banner, and shoot them if they knew the lyrics beyond the first verse!
It was something like Are you as smart as a 5th grader?
A question would be something like "Who was the 5th president?" and the answer was "Benjamin Franklin" or similar. :)
Implicitly, I suppose that makes the lights on the windward side blitzen.