Lol. Reminds me of the time I attacked a Dutch ship (neutral at that time) thinking it was a French - you know, blue white & red tricolour. Except that the Dutch flag has them horizontal whilst the French one is vertical.
To compound matters, it was my son who made the observation.
"Dad, is Holland an enemy yet?"
"No, why?"
"Then why are you attacking a Dutch ship?"
Fortunately I was surfaced & using the deck gun, so the damage wasn't too bad.