This post is kinda directed to pjalne, since I read up on the war cartoons on his site.
I remember watching Cartoon Network a few years back and they were doing War Propoganda. What's making one cartoon in particular especially hard to find is the fact that CN has aired about three of these same shows, all on Toonheads, all with the same theme.
The one I'm thinking of ends with Hitler emerging out of a pile of rubble, exclaiming "Nazi's are the cwaaaaaaziest peoples!" and then falls.
I can't find it for the life of me, but I found "You're A Sap, Mr. Jap" in my search, so it was kinda worth it :D
I know that cartoon. it has the Gremlins of the Kremlin and they make Hitler's plane crash, while singing a little song. When he goes into the ground, the plan's wing falls on top of him, and it looks like a tombstone. It was a warner brothers cartoon.
Damn, Jixby beat me to it. I've got a couple of pictures of on my site, I'll try to dig them up. Also, make sure to keep your eyes open this February, when Disney will be releasing all their war cartoons on DVD. There we go: