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.
The CTEA amended the Copyright Act by extending the term of protection for works currently in their renewal term from 75 years to 95 years. Under the new law, any work published in 1923 (which would have otherwise fallen into the public domain on January 1, 1999), will now be protected until January 1, 2019.