Cambodia is quite safe for those who support the dictatorship. It is the job of the police to make sure that these people are safe from those who do not support the current social system. In other words, it is the job of the police to make the streets of Eugene, Oregon safe for those who are driving home so that they can watch television. It is the job of the police to make sure that those who support the system are not confronted by those who are discontent. The police response was unprovoked, and unnecessary.
Nobody wants that.
I ask you, Bob, to reword that sentence just slightly. I am implying that most people are not you, and do not enjoy the social position that you have. If you want a militarized police presence, and a terrifying show of police force, then request that the police be at your home next time they feel the need to gear up. Unfortunately, from each other. You may live your life fearing your fellow human beings, but I refuse to use that as a justification for police violence.