These were *recent* compositions, songs that were written and popularized in the lifetimes of the parents and grandparents who took their kids to the movies to see Mickey shorts like "The Barn Dance," "The Opry House" and "The Jazz Fool." The ability to plunder this music at will was key to the success of Mickey Mouse and Disney. Think of all the Mickeys and Disneys we've lost by locking up the public domain for the past half-century!
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