Whats Schiffty trying to say here ?

As fall approaches, let’s recall how Longfellow once voiced his hope for America, and make that vision a reality:

“Sail on, oh ship of State! Sail on, oh Union, strong and great! Humanity with all its fears, with all the hopes of future years, is hanging breathless on thy fate!”

https://twitter.com/RepAdamSchiff/status/1306271917775740929

(UK timestamp)