Considering this film has nothing to do with the Civil War, or patriotism of any sort, why is it called 'Yankee Doodle Daffy'? Because it was made in 1943. That's about the only reason they needed. America was at war, and this resulted in such memorable films as 'Yankee Doodle Refrigerator', 'Yankee Doodle Charles Darwin' and 'Yankee Doodle Small Bump in the Road'.
Seriously though, for those who like seeing Bugs and Daffy in drag (something which they were oddly inclined towards - especially Bugs), this is a considerably better short than, let's say, 'Waikiki Wabbit'. At least it has a plot that's original and doesn't involve hunting.
Daffy is the 'agent' of a child prodigy, and desperetaely tries to convince Porky to sign him. Porky is more interested in going on vacation. In desperation Daffy personally demonstrates all the things the apparently inert kid can do, including his Carmen Miranda routine, as seen in the profile picture.
Pretty funny. Only just makes three stars from me, but it's not too bad at all. It's nearly all set in one room, so Freleng doesn't perhaps get to stretch his legs, but then again Jones's legs ended up being longer anyway.