Early in the formation of the PLO they started blowing up Israeli malls, schools, kindergartens, restaurants, sports arenas, basically any public place. This kind of tactic was not widely known at the time. Most of the Muslim world cheered them on and even supplied them with bomb making material. However, this was destined to come back to bite them.
It was only a matter of time until the PLO started using this tactic on each other for political gain, and on their neighbors if there was some dispute they were angry about. This tactic was quickly picked up by other terrorist groups. Now today, as we know, Muslims are blowing up other Muslims and anyone, all over the world. That is how this kind of thing evolves.
The Democrats are actively cheering these mobs on. They are inciting and encouraging them. But what happens when the 'mob' becomes angry at Democrats for not doing their bidding? The Democrats have opened a door which will be very hard or impossible to close. It is only a matter of time until the mobs turn on them.
That is how mob rule and mob anger evolves. Once the Left is taught the this behavior is appropriate, and that is how to get your way, it is only a matter of time until they begin to use it on each other and on Democrats they disagree with. That is a fact.