But I think we know from history, and other (attempted) authoritarian takeovers, that it only gets worse until people stand up and push back.
It's in their best interest to make everyone feel there's nothing they can do, there's no use in protesting etc etc.
I do think it works! And in addition to protests in the streets, and strikes, I think consumer boycotts would work. If a percentage of people stopped buying anything other than the necessities a lot of US companies would really feel it.