To the question 'where did the destructiveness come from?': it was there all along. What was once dinner party nihilism has lost it's inhibitions. The the riots are a 'coming out party' for all the doctrines taught in many a school.
The pro-Antifa leanings of politician's relatives reflects a deep cynicism of the liberal project. They are convinced everyone is as corrupt as the people they know.
And their response to this guilty knowledge is despair. Burn everything down. Go back to year zero. Free me of my shame. It a sociological murder-suicide.
One of the intriguing aspects of this outburst is a rage against religion, excepting those seen as hostile to Judaism or Christianity, that seems part of the drama. There is a special odium reserved for it, a kind of ritual desecration, which is key to understanding it.
That "tell" indicates this is not just about a man murdered by the Minneapolis police. This is about something deeper; that although the disquiet may die down having exhausted the immediate fuel the crisis will last a long time.
