

You have people like that everywhere.
They’ll stop acting out when they understand there is a not insignificant risk that they will be on the losing side and there will be consequences in a independent court that won’t look kindly on their actions. That’s if they don’t get caught before that and get to experience a symmetrical response.
If we ignore Polish solidarity, the fall of the Berlin Wall and the Romanian Revolution of 1989, protests against the Soviet Union started in the Baltics and quickly to other occupied countries.
The protests eventually even reached Moscow, with estimates of protest size ranging from 200 K to 500 K.
I will note that US population density isn’t that much lower than in Ukraine (38 per KM2 versus ~70 per KM2 in Ukraine). Assuming there are 4,500 KM between LA and NY (and 2M persons per 675 km) around 13.3 million people to replicate the Baltic Way, a mere ~4% of the population, compared to 25% participation rate in the Baltics as a whole (that would be about 80 million for the US population).
There are of course many differences between Warsaw Pact/USSR and modern US (with the issue that the Soviet economic system was collapsing and was irreversibly discredited), but that’s always the case with any situation.
The bigger point is that it’s never easy and successful anti-regime protests find a way through the challenges. Sure there is some measure of luck involved, and you have to take risks, but that’s true of literally anything in life.
And yes, the decline of democracy is a global issue. The old system/model is clearly reaching a breaking point. “The old world is dying, and the new world struggles to be born: Now is the time of monsters.” We’ll get through it. My only hope is that this breakthrough won’t take 50 years when I’ll be in my 80s.