I’ve always thought he did it to deliberately embarrass the United States.
Both Obama and Michelle do their ‘poke you in the eye” stunts deliberately to embarrass the United States.
Look at Michelle’s behavior. She put her arm around the queen, she wears bizarre clothes intentionally, and fails to follow protocol. Barry chews gum, screws up the toast to the queen and behaves like an oaf - except when he is in Saudi Arabia.