‘The Joker’ strikes a chord with more of us, than would condone the behavior of the protagonist.
Most times, we like some other ‘Joker’ to do the dirty work which would lead to the results we may subconsciously desire.
Most of us don’t like authority since our time in school. The rest of us choose to go across and aspire to authority. Few of us become authority figures long after school but even in school, there are bullies.
A breakdown of order results from a cathartic release of emotion from people who may have been bullied by authority; by teachers, bosses, cops or others.
It is an unloved and uncared for people who express themselves by looting and burning. They would like to destroy all symbols of authority but also the symbols of progress which justifies all authority.