Okay, that’s the opening ceremonies for the 1984 Winter Olympics in Sarajevo. “SAD” is Yugo for “USA.”
IIRC at the 1976 opening ceremonies in Montreal the brains at ABC assumed the US would be arriving in the stadium when the letter U had been reached not realizing the order would be using the French names for countries. Low and behold in comes the US with the sign saying Etats Unis just when ABC had cut to commercials.