On the day the Steelers clinched their second straight superbowl appearance, the streets of Pittsburgh were suddenly thronged with people jabbing their forefingers at a wintry sky and screaming. "We're number one, we're number one!"

It didn't seem to matter that day that the teachers were still on strike in Pittsburgh, that there had been no public education in the city for weeks, that millions of lives were feeling dislocation and damage; the Steelers - hyped as a mystic extension of the city - had won to show the world that the Iron City was "O.K., Jack," and deserved to be plugged into the national happy news network. For the moment, at least, it was a hero city of super people.

Those cries of "We're number one!" from major league cities and from high school gyms, have been described lately by social scientists as symptoms of the growing need of Americans to identify with the tangible and respected organizations; the increasing fragmentation of American life has made sports fandom a hook to hang onto.

More and more commentators have begun describing spectator sports as "the opiate of the people," as the "modern bread and circuses" and as the nation's "real religion" (while describing religion as America's real spectator sport), as if it were a '70s phenomenon sprung full-brown from the swollen coffers of the television networks, instead of a logical progression in the growing cultural importance of sports as a shaper of ethics, values and definitions.

Since the industrial revolution, the playing and watching of competitive games have been promoted as healthful activities for both the individual and the nation. Youth will develop courage and self-control, while Age will find blissful nostalgia. Or so we were told.

Families will discover new lines of internal communications, and immigrants will find shortcuts to recognition as Americans.

Industry, the military, government, the media, have promoted this faith in sports, and in so doing have imposed the values of the arena and the locker room upon our national life.

"Only winners are truly alive," said George Allen, formerly of the Washington Redskins and one of the all-time winningest coaches and a friend of presidents. "Winning is living. Every time you win, you're reborn.When you lose, you die a little."

There are dissenters, of course, more and more these days, ranging from parents trying to defuse the tense competitiveness of Little League programs to such sports radicals as Dave Meggyesy, the apostate all-pro linebacker, who said: "Football is an attempt to sell a blown out, smacked out people fighting inflation, the exploitation of their work, of their earth, that our system is still socially, economically and politically viable."

Heretic or defender of the faith, or nonparticipant, there is no escape from the impact of sports.

Traditionally, sports has acted as the first separator of the sexes; sometime soon after kindergarten, half the population - the girls - were cut from the team, literally or symbolically handed the majorette's baton and told to prepare for their careers as encouragers of men.

In recent years, the resurgence of the women's movement has significantly increased the number of females who participate in sports, but equality on the playing fields is nowhere near as prevalent as one might guess from the current hype of female sports stars.

From the middle grades on, boys are divided into athletes and failed athletes, worthy and unworthy, just at a time when they are most confused about their bodies and their relationships with their peers.

Most Americans, early winnowed from organized sports, either turn away from sports entirely, or become avid fans, a pastime encouraged by daily newspapers (which typically fill 25 percent of their news hole with sports results and gossip), by television (for whom sports programming and revenue is a mainstay), and by the ritual man-chat that makes sports our most common currency of communication.

Those who have survived all the cuts to make a world-class amateur team or a professional club have beaten odds that have been figured at one in a thousand. (Even then, success is generally short-lived - few pros spend more than five years playing for pay.)

They have usually sacrificed the chance to develop themselves socially, emotionally and intellectually, so narrow is their specialty. As Mel Rogers, a black high school basketball coach in Louisiana once pointed out, a boy who devotes his life to becoming president of the United States, even if he fails, will pick up enough experience and information along the way to make a successful and fulfilling career. A boy who devotes his life to becoming center for the Philadelphia 76ers had better get there if he expects to get anywhere at all.

Athletes are seemingly lionized in our society, but the adulation is superficial and comes mostly from children, groupies and the adult male "jock worshipers" that athletes hold in contempt. People usually want something from the athlete.

"Thousands of people who don't know me," says Bill Bradley, the Rhodes scholar who played 10 years in the National Basketball Association, "use my participation as an excuse for nonaction, as a fix to help them escape their everyday problems."

If the pro athlete sometimes seems "ungrateful" for this ephemeral and hypocritical celebrity status, small wonder that the black athlete, who has been most cruelly used by the sports industry, has led the way in demanding more concrete rewards in the form of super salaries. Spencer Haywood, the 19-year-old hero of the 1968 Olympic basketball team, set some sort of record by jimping from one college to another, then suddenly turning pro, then jumping to another league.

It was very hard to argue with his credo: "If you're from the ghetto, it doesn't matter what you do or how you get it, only if you got it. What loyalties you got? To your family. To your (black) brothers and sisters. But to basketball? To some team? Forget it."

Sports is a socializer for work or war or depression. Listen to the historian, John A. Krout, prepare us in 1929 for tough innings: "During depression, with thousands out of work, sports helps refocus our attention on the Great American values and ideals, and also helps us remember that life does not begin and end with the dollar."

Forty-five years later, a Miami Dolphin lineman, Norm Evans, prepares us for the new spirituality: "I guarantee you Christ would be the toughest guy who ever played this game . . . Jesus was a real man, all right . . . aggressive and a tremendous competitor . . . I have no doubt he could play in the National Football League . . . He would be a star . . .'

Even in golf, tennis and bowling, the sports with the greatest spectator-participant interface, the media thrust has been consumerism - the clothes, money and strength to buy more - rather than the joy of games.

Perhaps it is the lingering Puritan influence or the work ethic that compels us to justify our leisure, to make of sport a metaphor and a lesson and a preparation rather than a healthful high, the most fun a body can have in public.

The emphasis on the discipline of aport, rather than the creativity, and on spectatorship rather than participation, has made sports into a work camp. Those who would break out to truly play have been made to sound radical.

"For starters," wrote the distance runner, Bruce Kidd, "we should stop preaching about sports' moral values. Sport, after all, isn't Lent. It's a pleasure of the flesh."