This is a Tom & Jerry "war" cartoon with Jerry in the war mode pulverizing hapless Tom. Right from the beginning when he's tossing "hen-grenades" (eggs) to the end, he's using all kinds of objects as warfare. There are bunch of clever references to war slogans but modified, such as "That Friendly Rat May Tell The Cat" as one of the old warnings to use to give folks about being careful who you talk to, etc.
Jerry, complete a bottle-cap for a helmet, also dive-bombs the poor cat, riding paper airplanes with firecrackers, until he's finally shot down but he parachutes with a bra and lands safely. He even uses smoke screens by dragging a bag of flour along the ground. - whatever he can think up to win the "war." It's all clever and very funny.
This is non-stop action with a patriotic ending. I have no argument about this winning an Academy Award for best animated short.