And Freedom of Speech and Expression allows me to stand beside you with a bullhorn and drown you out.
Noise ordinances can be applied. I find it to be a convenient tool to make the logistics of assembly much more difficult, yes. But it is written to apply to all sustained noise levels. With permits, one may be allowed exceptions like construction, street/park festivals, etc. and thus have a gathering. The hurdles for getting such a permit or evidence of patterns of politically-motivated rejections is the meat of the discussion there.
It uses both. Standing across steps with arms linked to prevent marchers getting through is both non-violent and legal. Defending one self, or others against people attacking you is legal, but not non-violent.
Not
entirely legal, no. It is
unlawful to prevent others free movement in public space. I would heartily applaud those willing to take arrest to make their point to do the chain and passively accept 1-by-1 arrest.
This is, in part, where the police failed. As soon as the entrances were blockaded, they should have been establishing a neutral zone, giving the blockers warnings (lawful orders of officers).
The blockers should have designated people to find ranking officers and explain to them that they will passively surrender, but the general idea is to drag things out. Then you get about an hour of chanting and singing by the supporters outside the perimeter while the ones taking arrest get loaded on buses to be processed and released with no charges because you have a legal fund and contacted the NLG (National Lawyer's Guild) in advance.
You did get a legal fund and call the NLG in advance, right?
(ambiguous 'you', of course :9)
ETA: This opens the door to blasting the police chief, the mayor, the city council, etc for using city resources to arrest innocent people who wanted to stop Nazis, etc. This makes the cop who truly is good at heart -putting cuffs on someone for sitting down so that bigots can have their rally- have to ask some deep questions about "which side are you on?" This is divide-and-conquer thrown back in power's face. This is how you win.
No one is condoning any use of illegal violence.
You may not be, but yeah, there is a lot of condoning of illegal use of violence right now.