Copland is a fine choice for best American composer and of course Gershwin was a genius. But William Grant Still should be part of the conversation. His first symphony was the most performed American symphony pre-WWII and just as American as anything Copland composed.

floor: There are many great American composers, I lean toward Copeland, but Ellington's longevity and breadth are astounding. He is beyond any other american composer.

Yes! Of course there's a lot of Billy Straham in the Orchestra's repertoire, but even Armstrong wasn't consistently excellent for five decades.

That said, there is something the claim that Armstrong is the American composer. Many of his recorded solos were not improvised but notated. His solo for "Cornet Chop Suet," for example, was copyrighted before the recording, even though it sounds like he made it up on the spot, because his playing can pull that off. And the list of artists influenced by Armstrong go from Coleman Hawkins to Little Richard to James Brown to David Byrne to Kendrick Lamar. I imagined he influenced 'classical' conposers as well but I can't think of anyone more influential.