[runn1ng]

I don't think Mickey Mouse itself is the main reason for Disney to lobby on prolongation of copyright.

If it was just Mickey, Disney would survive that somehow, but well, Hollywood started to be relevant in about 1920's, and Mickey was created in 1928, so it coincides very well.

[benologist]

Sonny Bono also played a part.

http://en.wikipedia.org/wiki/Copyright_Term_Extension_Act

"also known as the Sonny Bono Copyright Term Extension Act, Sonny Bono Act, or as the Mickey Mouse Protection Act"