The police are an illusion. Fat, semi-educated power-mad bullies are of little use when the shit hits the fan. What they do is provide comfort for those who have little to do with them. It's nice to see that black-and-white going on down the highway until you have to deal with one. The inability to reason, wielding of power for the sake of wielding power, the getting off on pushing around average citizens, that is what the police do.
Your average cop is completely unused to real violence and incapable of dealing with firm resistance. Your Hollywood stereotypes are full of shit.