This 16mm antiwar short starring Mickey Mouse was produced by Lee Savage (father of Mythbusters Adam Savage) and Milton Glaser (who designed the I ♥ New York logo) for the Angry Arts Festival in 1968. It was never sanctioned by Disney, but they weren't sued over it, either. The film was lost for decades, but resurfaced online recently. Warning: may be disturbing for children. Find out more about it in an interview with Glaser at Buzzfeed. Link