I don't think you know how thin and untrained our general law enforcement officer is to handle such situations. He is presently trained not to violate someone civil rights and is not trained to handle paramilitary operation. Even the SWAT teams are only trained to handle one or two stationary bad guys at a time.
You are talking about Marshall Law and Obama's 600,000 civilian service army that he is purposing. By that time there will be plenty who will be fighting the police. Order can only be maintained so long as the people respect the authority of the civil Government. Police Officers are the most visible and accessible repersentatives of a government, city, county, state, or federal.
I can tell you right now our local police can not handle that situation. 5 dedicated people can take my town of 50,000 from our police force. I use to work for them. There wasn't a dozen men out of a force of 125 I trusted with my back, most are there for the paycheck (as odd as that may seem) and the power of the badge and gun, and will run when the "S" hits the fan.