The Bern, IMO, has some blame for this riot. He and his campaign probably had nothing to do with it in a direct sense, but when The Bern knuckled under to the BLM-thugs last August he told them that thug tactics work. So the thugs are going to keep using their tactics against Trump (and probably against Cruz and Rubio) until the tactics blow up in their faces.
It doesn't take being a Trumpling to figure out that he isn't going to crumble or knuckle under to these thugs. Just as Trump has masterfully played MSM hysterical hatred into 10s of millions of $$ of free publicity, Trump will work to turn these thugs' tactics to his advantage.
DU-folk are so blinded by their hatred of all things R and conservative that few can conceive of this Chicago riot being a very short-lived, Pyrrhic, "victory".