Merrie Melodies - Fifth Column Mouse (1943, WWII Propaganda Film)

The Fifth Column Mouse is a 1943 Warner Bros. Merrie Melodies animated cartoon directed by Friz Freleng. The short was released on March 6, 1943.
The cartoon features a band of mice who engage in war against a cat. This a wartime propaganda film, with the cat symbolizing the Axis powers. A single mouse represents the fifth column, working for the cat and suggesting an appeasement policy.

References to World War II:
The cat is treated as the enemy and symbolizes the Axis. After the cat whispers his plan inside the dim-witted mouse's ear the cat's face briefly mimics that of a stereotypically caricatured Japanese, while Japanese sounding music is briefly heard. When the mouse agrees to fulfill the plan, he gives the cat a Nazi salute. The grey mouse represents the policy of appeasement, and the overall theme of the short is that the policy does not work against the Axis and will lead to ruin. When the cat's fur is shaved off, the first four notes of Ludwig van Beethoven’s “Fifth Symphony” are played; these notes were used by the Allied Forces as a symbol for "V" (for "victory") in Morse code; also, when shaved four tufts of hair are left on the cat's back - three short and one long tuft - equivalent to the Morse Code dit-dit-dit-dah - which is the letter "V".

Near the end of the cartoon, the brown mice sing “We did it before and We can do it again”, a patriotic chant that was often used in American films during World War II. The song was co-written in 1941 by Tin Pan Alley songwriter Charles Tobias (who also co-wrote the Merrie Melodies theme some years earlier) as a response to the sneak attack on Pearl Harbor. During the song, a mouse version of the "Buy War Bonds and Stamps" poster can be seen.