Last week Her Honor Jane Byrne, mayor of the great city of Chicago, moved with the kind of decisiveness that makes life in this great democracy so immensely worthwhile. Distressed over the level of barbarism in Chicago's Cabrini-Green housing project, she actually established residency in the place and began moving her household -- her wardrobe, her hair curlers, her husband -- into a two-bed-room apartment, which the Chicago Housing Authority has painted and furnished from the showrooms of Sears and Goldblatt's.

Some 15,000 souls live in Cabrini-Green. Since New Year's Day, 10, possibly 11, have died from the gunfire that regularly resounds down the corridors and from skillful snipers overhead. Thirty-seven have been wounded. I do not have at hand the statistics on rapes, muggings and other acts of intimidation, and anyway statistics from a war zone like this are not reliable. Police believe that the trouble is caused by 75 to 100 rival gang members extorting protection money from these poor people and trafficking in drugs and prostitution. Police also estimate that there are 2,000 gang "sympathizers" who, from fear or admiration or sloth, store weapons for gang members and provide them windows from which to fire away. From this we can deducts that the elimination of 100 troublemakers would not pacify Cabrini-Green. With so many now collaborating in degeneracy, it is apparent that the community had descended into hopeless savagery.

Ever since the mayor made her decision, the wiseacres around city hall have entered into learned speculations about why she did it. Some have personally informed me that it was the fragrance of spring. A large, more credible group insists that is is merely a stunt. They remind us that Chicago mayors now have to go beyond boodle, sinecures and good works from the tax assessor to maintain the halo above city hall. Now the local Pericles must pirouette and sing and ride garbage trucks, preferably into neighborhoods where garbage collectors fear to tread.

Finally, there is a lady journalist who believes that the mayor is simply displaying womanhood's natural superiority over the male of the species, a superiority that has been repressed for thousands of years and would be repressed today were it not for modern birth control and the eruption of an amazing generation of Superwomen within the American middle class. Such is the range of opinion in our nation's "Second City."

My view is that the mayor is moved by confusion and little more. She is a pious woman and an exemplary believer in our civic religion. According to the tenets of the faith, every American is au fond just like Jane Byrne. All have the same longings, the same fundamental capacities and the same mellow vision of the good life. Some achieve it and some do not. What is important is that those who make it demonstrate to those who fail that they "care." What is necessary is that those who make it "communicate" and dream up therapies to bring down on the heads of the Jane Byrnes who have not made it.

Cabrini-Green is a showplace for all the therapies of our civic religion. In the late 1960s, it was what we called a neighborhood, but it was a rundown neighborhood, and according to the piety of the time, urban renewal was the proper response. Now it is a 70-acre wasteland, dominated by 23 towering buildings some as high as 19 stories. Eleven years ago, two police officers were gunned down while walking their beat. So an additional $22 million was spent, most of it in accord with the pieties of that time. Decentralized, resident-controlled management offices were put in. New landscaping was provided, and the courtyards were blacktopped. Now 79 percent of the households receive some sort of welfare. Children outnumber adults by more than two-to-one. Of the families with children, 88 percent are one-parent households.

Has the civic religion brought the good life to that poor Chicago neighborhood now called Cabrini-Green? The same members who flock to the place and some of their sympathizers obviously think so, but others are more like Jane Byrne. And so the civic religon dictates a new therapy, "personal involvement." "Something," the mayor declaims, "has to be done. I truly believe when a mayor is there, everything works better." The mayor brings with her a huge police detail, the attendant journalists and camera crews. In 20 years, the civic religion has taken us from urban renewal to martial law. Naturally it is not called martial law and naturally the reports are optimistic. "She is delighted with the new apartment and its furnishings," her ebullient news secretary, Ray McCarthy, sings. The move "already has had the desired effect -- street gangs . . . fled in fear at word of her coming," the UPI reports.

Will middle-class serenity finally settle on Cabrini-Green? Margaret Rose of Atlanta's Housing Authority remembers a similar move by Atlanta Mayor Maynard Jackson in 1974, and last week she declared "I don't know that it changed a thing." Mostly likely it did not. The problem for Mayor Byrne and for Mayor Jackson is that they have placed their faith in a civic religion whose fundamental premise is very shaky. Not all the residents of Cabrini-Green are just like them and neither social engineering nor patriotic incantations will change that truth.