The force's composition suggests that it was being sent in expectation of a fight. One possibility was that the Uruguayan government would be unable to make Admiral Graf Spee leave Montevideo. Another was that the ship would try to escape toward Argentina. In either case, Ark Royal's aircraft could attack the German ship in harbour or at sea. An attack in a neutral harbour would break the law. The closing joke casts the Royal Navy as more interested in making laws than worrying about breaking them.
Notable Point · 1:40-2:15
Ark Royal and a possible attack in neutral waters
Force K appears to have been sent in expectation of a fight if Uruguay could not make Admiral Graf Spee leave Montevideo or the ship tried to escape toward Argentina.