The state of China and its willing supporters are the enemy. It would be senseless to beat someone on your own side.
Yes, protest is war if you're being attacked and invaded, the protestors have every right to slaughter their oppressors.
Are you suggesting the victim is "oppressors" to the protestors? Or, are you suggesting anyone from "The state of China" should be tagged as "enemy"? How do you define "willing supporters"? Did the victim attack protestors? How comes slaughter a human being (even if an enemy) becomes natural right in a civilized society?