Animator Chuck Jones tells the story of animating training films during World War II with Dr. Seuss, and why animation was a good medium for the cause:
"Here was the problem they had: if you took live action and you had a bunch of soldiers trying to act, they couldn't act, and they were unbelievable. If you took an actor and put him in and pretended like he was a soldier, the soldier audience knew they weren't soldiers, and and they didn't trust the film.”
Watch Chuck Jones' full interview, where he tells the stories behind his legendary career, including creating the Looney Tunes characters Bugs Bunny, Daffy Duck, and more.