Debussy wanted to distance himself from what he considered the emotional excess of the Romantics and instead wanted to write music that, through sound, created an ambience similar to that of the Impressionist painters and Symbolist poets of his day.
All books initially copyrighted in the US from 1964 through 1977 have had their copyrights automatically renewed (by law) and the copyrights are still in force. The initial copyright term was 28 years; the renewal was for 67 more years.
Works originally copyrighted between 1964 and 1977 are granted an automatic renewal term (See Extended Renewal Term) by the Copyright Act, without the necessity of the writer having to file a renewal registration form in order to preserve copyright protection, as was the case for earlier copyrights.