Baloney. They have no duty to protect anyone. Their job is to apprehend individuals AFTER a criminal act has occurred. Any action to "protect" amounts to prior restraint without probable cause. Law enforcement deserves a good paycheck for putting themselves in harm's way when dealing with the criminal element, but that doesn't make them any better than any other citizen. Our military services place themselves at far greater risk every day.
Their job is to apprehend individuals AFTER a criminal act has occurred.
That is how the police system was designed to protect us.