The net effect, however, is to make sure ~4000 people will have less choices in the future, and a more miserable life.
Looting and burning a city on a large scale, of course, will always be one of the remaining choices. Furthermore, the more miserable life part will provide extra incentive to do so.
They are admitting to using two year old footage to identify people in a crowd, who are associated with people who turn violent.
It implies that they can and will dedicate that much time and power to put you on lists and possibly harass you for exercising your freedom of speech and assembly.
Given the relationship between the police and protesters, I wouldn't want to suffer the repercussions of being in their systems as one.
The result is that I'm less likely to become politically active out of fear of being identified and associated with subversives in the eyes of my government.
Looting and burning a city on a large scale, of course, will always be one of the remaining choices. Furthermore, the more miserable life part will provide extra incentive to do so.