You say it is not justified and then almost qualify it as necessary. It basically tells eveyone that you did not mean is was not justified.
First off...justified <> necessary.
Second, scope matters. I don't believe these riots happen if not for other recent events.
Third, there is no justification for the distruction of property owned by people who had nothing to do with an event. That doesn't stop me from looking at history and seeing what happened in order to affect societal changes. I don't think there is ever any justification for any soldier to die...that doesn't keep me from understanding why they die.