The tried and tested ways of expressing dissent don't work (if they ever did). The capitalist system has shown that it doesn't work, despite all of the promises of trickle down economics and the like, the majority are getting worse off while the minority are getting fatter and richer. The latest "solution" is to use more public money to pay people who are already fabulously wealthy to carry on with business-as-usual (literally). These are precious funds diverted from needed social programs.
The industrial system is also showing that it doesn't work: anthropogenic global warming/ climate change is destroying the habitability of the planet. The industrial system also depletes future resources and contaminates the soil, water, air and trophic networks. Yet the governments will not endorse a change in the industrial system.
The political system is not working: international law is a joke, the so-called "good guys" have been shown to have transgressed international law by invading a sovereign nation, disposing of the leader they originally installed and supported. We export "democracy" although even locally it is a broken, hollow shell of ritualised ceremonies without substance or public representation.
The rule of law is also broken: police are political thugs paid to maintain the status quo, like attack dogs, without any accountability, and go out of their way repeatedly to incite and provoke reactions so they can justify their over-bearing aggression and over-zealousness.

In light of all of this, a few broken windows in some bank are minor issues, but are swooped down upon for media-fuelled attention to make a big fuss over. The banks should have been burnt down, the cops should've been beaten up, the state should've been dismantled and the industries stopped. But none of this happened, out of restraint, only out of restraint. The time will come when such restraint no longer applies because we are each gradually becoming enemies of the state, regardless of how we may have initially started out along this road of dissent.

The state reserves its sole right to use violence, but then they call it enforcing law and order, or engaging in warfare for just causes or other such nonsense. When the public refuse to support that idea that the state reserves the right to use violence as its sole mandate and takes back their power to use violence as one tactic of many, the state had better watch out. We have pretty much run out of our options, no thanks to the police and the politicos. Perhaps it is to violence that the system will listen, in which case the time for the state to listen is almost upon them.