Attytood: A police coup in Ferguson, Mo.

THE TEAR GAS was essentially still in the air in the fall of 1968 when the National Commission on the Causes and Prevention of Violence - yes, that was a thing - formed a working group to probe the civil disorder that had just occurred at that year's Democratic National Convention in Chicago.

It was there, some will recall, that police in baby-blue helmets clubbed and dragged bloodied war protesters through the streets, while TV viewers looked on and crowds chanted, "The whole world is watching." To describe the incomprehensible scenes, the so-called Walker Commission coined a new term. They called it a "police riot."

There has been no police riot in Ferguson, Mo. - not yet, anyway (and hopefully never). But what was happening last night in the working-class suburb of St. Louis was, in some ways, far worse. A tense situation in the aftermath of Saturday's fatal shooting by a police officer of an unarmed, college-bound 18-year-old named Mike Brown has been made worse, night after night, by brutal, boneheaded policing that makes one wonder if Birmingham's Bull Connor has been reanimated.

I thought I was losing my capacity to be shocked - but events in Missouri late yesterday crossed a frightening line, one that makes me pray that this assault on fundamental American values is just the aberration of one rudderless Heartland community, and not the first symptoms of a nation gone mad with high-tech weaponry to keep its own citizens in line.

The people in charge of a large American community were systematically shredding the U.S. Constitution last night. It was nothing less than a police coup.

The Bill of Rights guarantees that all citizens have the right to assemble peacefully. And yet residents of Ferguson who gathered to protest under the bright August sun were met with a midsize army of militarized cops, ordered off the public right-of-way, and ordered to go home, under the glare of a rifle mounted on a tripod. In a move that even George Orwell would not have believed, cops with loudspeakers insisted to the crowd: "You have the right to peacefully assemble - from 25 feet away."

The Bill of Rights guarantees freedom of speech - but over these successive nights, citizens who've tried to speak out have been hit with tear gas (in at least one case, at a private citizen on his own lawn), then rubber bullets, as well as wooden pellets fired from guns.

The Bill of Rights protects the right of a free press - but apparently not in Ferguson, Mo., not yesterday. Reporters from the Huffington Post and the Washington Post were arrested by cops inside a McDonald's (!) as they were trying to file their reports; the Washington Post's Wesley Lowery, an African-American, was slammed into a soda fountain. They eventually were released (one small step for mankind), and when Lowery was asked if he was more scared of the protesters or the cops, he answered: "Easy answer: I'm a black man - the police."

Other reporters, including two who happened to be black, said they were denied access to a news conference. Trymaine Lee, a former Daily News intern who went on to win a Pulitzer Prize, said on Twitter: "I've been told to disperse and go to my residence . . . "

America's political traditions insist that the public has a right to know what its government is doing. This, too, has been ripped into a thousand pieces in Ferguson, Mo. The name of the officer who shot Mike Brown has been shielded from the public, and so have most basic facts of what occurred last weekend. A report from the medical examiner was censored to keep the public from even knowing how many times Brown was shot. What is Ferguson covering up?

There is a lot to talk about in the days and weeks ahead. For starters, authorities - not just in Missouri, but around the nation - are going to have to explain the obscene (and obscenely expensive) overmilitarization of American police departments, weaponry now aimed at the communities that these officers had sworn to protect and serve.

Americans should not have to see TV news that looks like it's coming from ISIS-held territory in Iraq or Kandahar, until we see the McDonald's arches in the background and realize that we are just 15 minutes from Busch Stadium.

And there will have to be a massive conversation about community policing - especially in Ferguson, a majority-black community where 94 percent of officers are white - but also anywhere where cops are seen as suppressing communities instead of protecting them. And there must - and one cannot emphasize this enough - be real justice and accountability for the murder of Mike Brown.

But that is not the priority now. Now, someone with a cool head and the utmost respect for the U.S. Constitution - and frankly, I'm not sure who that is - needs to take control of the situation on the streets of Ferguson.

The first move is to end this police coup, immediately.