Answer:
The song gets more intense and louder (crashendo which is a music term for getting louder) because Hamilton is referring to how he sees the bigger picture. He realizes that "the action in the street is exciting, but Jesus between all the bleeding and fighting I've been reading in righting. We need to handle our financile situation. Are we a nation of states? What's the state of our nation". He understands that there is more to the revolution than simply fighting.
I hope this helps!
Btw I LOVE Hamilton!