People seem confused by what the police are doing in Ferguson. Some people believe that the police are within their rights to arrest people for swearing or failing to move on when ordered to do so. Others believe the police resemble a paramilitary force. Police vary in different areas and react differently depending on whether they perceive someone as a threat.
Look at the news reports. Try to get them from several different viewpoints, not just conservative sources like Fox News. You will see from the videos that the police in Ferguson are indeed equipped like a paramilitary force. They are also routinely violating the rights of Ferguson's citizens by assaulting them, arresting them for using obscene language or just for standing in one place. The police have been recorded threatening to kill journalists and they have arrested both journalists and humanitarian workers, like the National Lawyers Guild monitors who simply observe police behavior.
Some people claim the police are just protecting citizens from the demonstrators. We don't know what the police are trying to do, but we know what they are doing. They are quite clearly violating the law and the Constitution. They are using terror tactics against US Citizens who are within their rights of freedom of speech and assembly. They are also using weapons against innocent bystanders. Sound cannons affect everyone in the area. Tear gas can force people over a mile away to leave their homes to breathe fresh air. This is a major reason why tear gas (and other poison gases used by police) have been banned in warfare by the Geneva conventions, because they harm everyone nearby, not just armed combatants.
As far as the police protecting themselves from heavily-armed individuals, there has been a but single incident of a policeman wounded by gunshot in Ferguson. On the other hand, we have numerous pictures of police in riot gear aiming rifles or shotguns at demonstrators. It seems the armaments are much more prevalent on the police side. The police fire tear gas and other poison gases, as well as rubber bullets. They also arrest people by slamming them to the ground hard enough to injure them.
The demonstrations are a textbook example of what came to be called a "police riot" after the police attacked demonstrators at the 1968 Democratic Convention in Chicago. In a police riot, it is the police who are the instigators of violence, not the demonstrators. In many cases, the demonstrators are not armed, and certainly never to the extent that police are armed.
There are many other ways for the police to interact with demonstrators. The best way is to negotiate with them. All along, the demonstrators have been demanding that the police officer who killed Michael Brown be arrested and put on trial. This is a simple demand. There is nothing illegal about such a procedure, though it may violate police regulations. Even if it does, there should be a high priority placed on civilian safety. Complaints against police, who are hired to protect the people they are now assaulting, should be handled promptly and in an orderly manner.
The Ferguson Police Department has behaved throughout as if they are an occupying army. This must not be tolerated.