Over the past 25 years, it is hard to think of two public figures who have more consistently and constructively addressed the major concerns of this nation than Daniel Patrick Moynihan and Bill Moyers. That both of them now have chosen to focus on the breakdown of the family, especially the black family, strongly suggests that the rest of us should pay attention.

Moyers' documentary on CBS Saturday night brought to life the painful reality of which Moynihan, the senator from New York, wrote in his newly published book, "Family and Nation." That reality is that a growing portion of America's young people -- a large majority of blacks and more than one-third of whites -- will spend a substantial portion of their first 18 years in a "family" with no man as its head.

Many of them will have started life as children born out of wedlock, often as children of females still in their teens. They are part of a "culture of poverty" that mocks the economic gains the rest of us are enjoying.

Alice Sondra Jackson, one of Moyers' subjects, was 20 when her first child was born. She had graduated from high school, taken a year at a business school and was working steadily when she got pregnant. "I wanted to be a mother, you know," she said. "It was exciting to me. I just thought I'd have something of my own, a little child that's gonna call me Mama. . . ." Two more pregnancies followed in the next three years. Alice now lives on welfare, though she says, "It makes you lazy just to sit around and wait for a monthly check to come in."

The father of her children is Timothy McSeed, who has three other living children by as many other women -- none of whom he supports. Born to a 16-year-old unmarried woman, Timothy is a high-school dropout who has not worked in almost three years. He will marry, he says, when he can afford "a big wedding" with all the trimmings.

Stories like this are what made Eleanor Holmes Norton, a black scholar, lawyer and public official, say, "Repair of the black family is central to any serious strategy to improve the black condition."

But not just the black family. As Moynihan writes, "By the mid-1980s, it was clear that family disorganization had become a general feature of the American population and not just an aspect of a frequently stigmatized and appropriately sensitive minority community."

In 1965, Moynihan described an "approaching new crisis in race relations" because one-fifth of the nonwhite families had a female head of household. Today, he notes, "single-parent families with children accounted for more than one-quarter of all family groups -- white, black, Hispanic, et al. . . . What was a crisis condition for the one group in 1960 is now the general condition."

What lies ahead for the growing number of one- parent children is indicated by a 1980 Kettering Foundation study cited by Moynihan. They are poor students; 40 percent are rated low-achievers. They are sick more often, absent more often, more likely to be truant and twice as likely to drop out short of graduation. At which point, they are far more likely to be unemployed -- and perhaps unemployable. And procreating another generation like themselves.

So what is to be done? Everyone acknowledges that to the extent the problem is most severe in the black community, as it is, it challenges the total leadership of that community -- its stable families, its churches and its growing middle class.

But the larger society cannot turn its back on the problem, for it is our problem too. Moynihan, perhaps overoptimistically, suggests that both conservatives and liberals may be able to see the need for something he has long championed, a "family policy." Such a policy would consciously shape every area of government -- taxes, Social Security, elfare, housing, anti-crime and anti- drug measures -- to strengthen incentives and supports for two-parent families.

It remains to be seen whether that concern will inform decision-making in this age of budget-cutting. But even if an immediate response is unlikely, the challenge must be posed, as Moyers and Moynihan have posed it. Carolyn Wallace, who with her husband runs a community center in the heart of the Newark ghetto, closed Moyers' program by assuring him that preaching greater personal and social responsibility was not in vain.

"They won't listen to me," Moyers said.

"It doesn't make any difference," she replied. "You've got to say it anyway. They may not listen to me, either. But . . . if you say it in your corner and I say it in my corner, and everybody's saying it, it's going to be like a drumbeat, and sooner or later it will sound. . . . I think it's going to surpass color. And you're not going to be safe, I'm not going to be safe, and nobody's going to be safe unless we all send out this drumbeat -- hey, let's deal with it. Let's deal with the problem."