Paused at 3:23. A "protest" that gets people killed is not a protest, it's a riot. Riots are violent groups and need to be quelled by the arm of the law. If the law (being police) is insufficient, as seems to be the case, then force will escalate to the point it needs to in order to keep the peace. No matter how angry you get, you do not have the right to destroy other people's property and lives. Your rights stop where other people's rights begin. Words are met with words, and violence is met with violence.
It's not even a complex question. What do you mean you called in the army when cops were murdered in the streets? I don't see any part of that which suggests rioters were shot and killed. So the violence thus far has been entirely one-sided.