Actually, that is exactly what police are supposed to do in a riot. They control the crowd. If anyone in the crowd tries to engage them close up, they force them away or otherwise take actions to stop the actions of that individual.
Your last sentence is particularly stupid (sorry for being so blunt there). How does the officer know what is the correct amount of physical force to use in pushing the guy back? Should he just tap him lightly and say "get back?" You do note the police told the guy repeatedly to get back and away from him but he ignored that and continued to try and engage them.
So, the guy isn't listening to their orders and continues to do what they are telling him not to. What should they have done? Beaten him down instead? A firm push by the officer seems a totally appropriate escalation after the guy shows he isn't listening to their verbal commands. It's the guy's fault.
That was not a riot, you asshole.
No cop should be allowed to do what happened there.
But, obviously you are too full of your moronic self to recognize it.
