POLAROID SAW IT. So did Abbie Hoffman. And Roone Arledge capitalized on it, as did Fabian, John F. Kennedy, Walt Disney and thousands of farmers in the hills of Colombia.

It is the Baby Boom, the much celebrated bufge in the United States population, sired by millions of World War Two veterans and their contemporaries. They-those young adults born between 1945 and 1955-are the one certainty in the American future. Clever investment strategists know that those "boomers," now frolicking in Club Med or their favorite singles bars, are buying homes (housing boom, now underway) and will begin retiring in about three decades (projected Florida real estate boom, ca 2010).

David S. Broder, professional political trend-watcher for the Washington Post, sees the Boom too, and announces portentously at the beginning of his new book that "America is changing hands." As they swelled colleges in the sixties, grad schools in the early seventies and jogging tracks in the late seventies, the Baby Boom children are coming to city halls, state houses and Capitol Hill. In his latest book, Changing of the *uard: Power and Leadership in America, Broder profiles the top contenders to be leaders of the new era, the best and the brightest of the generation of McGeorge Bundy's, Dean Rusk's and Chester Bowles's children.

The basic facts seem obvious enough, but no one before Broder seems to have taken the time to explore them. The Depression and World War II will soon recede as the pivotal experiences in the lives of our leaders. An entirely separate group of influences shaped Broder's generation-in-waiting and the men who currently run the country. Broder's people, "immunized against the childhood diseases and exposed to endless hours of television," saw America slip from a position of unquestioned world superiority into the Era of Limits, American values crumble from a dependable, if not always righteous, code to a confused new national disorder. This generation watched-and in great measure caused-the demise of the great consensus of the 1950s and 1960s. Having seen the collapse of the old order, they must build anew.

And they are raring to go, Broder thinks. As they clogged academic admissions offices, throngs are now fighting for places in the political fast lane. Fairly oozing confidence in these young turks, Broder seems to have tried to interview them all-everybody. This desire to get at least a few paragraphs on every up-and-coming city councilor or county executive in the country is half of the book's most serious flaw. Broder boasts having interviewed 300 people for his 500-page tome; a selective paring of the number of people discussed would have streamlined a bulky text.

The other, more serious, half of the problem lies in the book's format. Broder says he wanted to let his politicians speak for themselves-and do they speak. The author's confidence in his subjects' political futures may be partially born out by their mastery of the Harmless Generalization, the Well-Intentioned Cliche and the Uncontroversial Piety. Normally a tough and inquisitive journalist, Broder lets answers like "If you look at the history of Western Civilization, the facts are pretty clear that man's progress is accelerated in periods when...we allow markets to allocate resources," (Rep. Phil Gramm, (D-Tex.) and "My job is helping the President keep his own commitment to women's issues" (Presidential adviser Sarah Weddington). In his desire to make all those interviews worth his time, Broder seems to have suffered a touch of the Elizabeth Drew disease: the uncontrollable urge simply to retype rather than rethink one's notes.

But for all his problems in his presentation, Broder has fashioned a remarkable assemblage of raw data on a generation, sprinkled with more than an occasional insight. Broder chronicles what he calls the generation's networks, "based on a net of shared experiences, triumphs, tragedies and misadventures, especially vivid to those who were there." He makes a convincing case for the existence of his seven networks (Organizers, New Right,Labor and Business-an odd pair. Public Interest Lawyers and Reformers, Women, Hispanics and Blacks) primarily by profiling their members. These networks work much as older, informal "Old Boys" connections functioned, but are based on conviction rather than social class.

THE PREPONDERANCE of Democrats in these networks will mean a resurgence of the reform spirit, Broder predicts. The dependence of the New Right on technical devices, the most notable being Richard Viguerie's mail operation, and its "lack of spiritual and emotional bonds-those network links-to the shaping experiences of this generation may ultimately deny the New Right the long tenure in power that its intellectual energy would otherwise be likely to earn it." When the Left learns the technical tricks of the mail-order and other games, the balance will shift.

But the left that returns to power may be so different from the New Dealers and their epigones that the term may prove a misnomer. With the shift in the nation away from the northern cities to suburbia, the west and even to the south, the goals of the reformers will change. And with an electorate that lives and votes by what it sees on television, the method too will vary. Broder talks frequently about change and leaves it at that; he does not pretend to know what kind of change. That's too bad, but at least it's honest.

DESPITE A RELENTLESSLY non-judgmental style (Broder seems to like a Marxist judge in Detroit and an Indiana housewife turned "right-to-life" activist equally), the author does manage to capture the political spirit of a generation. Acutely conscious of the current void in leadership and new ideas, they seem to be reaching out for new solutions-and, of course, new ways to get elected. Broder announces proudly his confidence in their ability to do so, though the 500 pages contain precious little in the way of new political thinking. At least, Broder concludes, "they have a crack at turning the country around...It will be worth staying around to watch." Indeed it will, just as it will be worth following up on Broder's fascinating political tip sheet for the eighties, nineties, and beyond.