"I must be good and glad and gay, for I'm a birthday child today" -- that was the required recitation at Sunday School, long ago in my youth, when your birthday came around.

That is the required mood for Inauguration Day -- faith, hope and especially charity to the two-legged character taking on the presidency. Sen. Edward M. Kennedy said it just right when he called on President-elect Reagan last month:

"I believe the American people now want cooperation. In that spirit, I came here to indicate mine." Some wiseacre reporter asked him if he still thought Reagan was a clone of Carter. Kennedy laughed. "Those days are in the past," he said, "and I'm looking forward to the future."

The soothing milk of amnesia tastes its best on Inauguration Day. Six months from now, we will be wondering what in the world happened to the high hopes of January. Thus the presidential drama swoops across the calendar, like a momentous diva pacing the opera stage, and follows a script as inalterable as the liberetto of Don Giovanni.

Someday, we must set aside a saga that has served us so ill in the past, from the high of great expectations to the pits of political despair. Might as well be now.

Like everyone else he ever met, I like Mr. Reagan. I'd like to have him over and watch "Little House of the Prairie" and tell stories. But he did not run for best friend.

As president, he will be dangerous, his dangers being very different from those we are familiar with in the cases of rigid, hard-driving presidents such as Johnson and Nixon, and very different from the main dangers his opponents were highlighting just a few months ago. For the benefit of next time, we ought to ponder how we picked him. And for the months ahead, those who back and oppose him ought to know what to watch for.

Reagan floated into the presidency on a recurrent tide that swells through politics with remarkable regularity -- the tide of reaction against too long and hard a time of troubles, too much worry, too much tension and anxiety.

Sometimes people want a fighter in the White House and sometimes a saint. But the time comes when all we want is a friend, a pal, a guy to reassure us that the story is going to come out all right. In 1980, that need found just the right promise in Ronald Reagan, the smiling American.

Echoes of similar elections were everywhere in the Reagan repertoire. "Smile, honey, smile!" his wife would whisper as he got set for the cameras. It recalled that lovable Lub, William Howard Taft, with his motto for 1908, "smile, smile, smile," coming in to help the nation rest after Roosevelt who counseled him to "let the audience see you smile, always , because I feel that your nature shines out so transparently when you do smile -- you big, generous, high-minded fellow."

Mike Deaver, Reagan's public relations man, announced after the 1980 election that "we'll have a return to normalcy," echoing that wonder of flatulent fellowship, Warren G. Harding, who invented the word.

Then there were Reagan's imitations of Franklin Roosevelt, the master reassurer and hoper in 1932, not only in such phrases as "the only thing the cause of peace has to feat is feat itself!" but also in the manner of Reagan's fireside chats, aping FDR's folksy radio style:

"I'd like to speak to you for a few moments now not as a candidate for the presidency but as a citizen, a parent -- in fact, a grandparent -- who shares with you the deep and abiding hope for peace."

Reagan's sheer personal likability in 1980 conjured Ike in 1956, Mr. Likable himself, easing the nation through the throes of suburbanization. And as Reagan stood before his party convention in 1980, the slogan of the day was plastered in great white letters across the platform: "Together -- A New Beginning," derived no doubt from memories of 1968, when another Republican won on the promise of "Bring Us Together."

So there we were again. The drama for 1972 had been the drama of combat, especially the shredding of the Democratic Party. Called for in 1976 were conscience and a revival of morals after a decade of political debacle; both Carter and Ford rang the bell for God and goodness.

By 1980, we were ready as a nation for a surcease of anxiety. We had had enough of bickering and preaching. After the shakedown to nominations, the public had one choice among three -- a moralist (Anderson), a fighter (Carter) and a reassurer (Reagan).

Reagan virtually had it from the start in his own party and in the nation after the cut-'em-up Democratic convention. John Connolly, the hot fighter of the Republican Party, won exactly one delegate to his national convention. o

Sen. Kennedy, after his Georgetown speech the fighter of the Democratic nomination phrase, was swamped by Carter, who then adopted Kennedy's losing style. The president, whose approval rating had descended to sub-Nixonian levels, worst in the history of the question, had to apologize to Barbara Walters for his "meanness," which nevertheless kept popping up.

Reagan, guided by his ad man, Stuart Spencer, kept his comforting cool. Spencer said of Carter, "The harder he gets, the softer we're going to get." s

When Carter and Reagan met, first at the Al Smith dinner in New York City and then in their face-to-face debate, Reagan managed to define himself as the apparent incumbent, outsmiling and condescending to his ill-tempered little pal Jimmy.

Reagan closed his debate with a question: "And, most importantly -- quite simply -- the basic question of our lives: Are you happier today than when Mr. Carter became president of the United States?"

Pat Caddell called the election "a referendum on unhappiness." His team's strategy -- to hit Reagan and "make him less grandfatherly, less genial" -- got nowhere, and Caddell's "fed-up vote" shaped what Elizabeth Drew called "a great national to-hell-with 'em."

In 1976, Carter won on a conviction that the White House ought to be swept clean of the trashy behavior Nixon exemplified. In 1980, Reagan won on an emotion, that happiness was down and needed restoring. Despite his defeat, Carter was able to keep people thinking he was a decent man, though flawed.

Reagan now has a much tougher task, it seems. For he has staked his fortunes on popular satisfaction -- on results, on actual improvements in the lives of citizens, not just trying or hoping or posturing. He is supposed to make it well again. That is very likely to prove difficult, if not impossible. The structure of power stands in the way.

Reagan's best bet for popular support in darker months to come may well be the fury of the radical right, whose indignant disillusionment with Reagan will help him gain acceptance with moderates. But his initial popular support is thinner than his "landslide" in the electoral college makes it look.

Reagan won in an election with the lowest turnout in 32 years. Only about one-fourth of the eligible voters bothered to vote for him. He has a modest majority in the Senate, but Democrats control the House, through which his novel tax-cut strategy must be played.

The bureaucrats in what Reagan called "the puzzle palaces on the Potomac" have their own ways with victors from out of town, as Jimmy Carter eventually learned. Reagan's knottiest problem, inflation, has proved incredibly resistant to reform, here and elsewhere throughout the civilized world.

And Reagan has no terrible social disaster going for him, no clear-cut trauma, such as the collapse that brought in Franklin Roosevelt, to put steam behind a burst of effective legislation in his first 100 or 200 days.

So far, Reagan has charmed Washington . Winning Washington -- and maintaining his fragile support with the press and public -- will take a good deal more doing.

The press and television will be crucial for Reagan. Intrigued initially with his novelty (vs. four more years of The Carter Family), the press will write for a while about the opening ceremonies and the emerging plans.

Then will come the inevitable "performance gap" stories, featuring bobbles and corruptions on the road to Utopia. Reagan himself will do well with fireside chats and televised addresses, but unrehearsed interviews and press conferences threaten to reveal even more areas of vast ignorance and mistaken perception.

The hit-and-run rhetoric of the campaign has its challenges, but they are nothing like the sustained and fact-anchored scrutiny Reagan will face as president. The alternative -- seclusion -- threatens the journalist's bread and butter, stimulating his furious imagination. The Reagans, both privacy freaks, never had much use for reporters, a sentiment sure to be reciprocated.

It seems clear now that no "conservative revolution" lends force to what Reagan will achieve in the coming months. Only 11 percent of Reagan voters decided for him as a "real conservative," and the polls say the main reason was "it's time for a change."

Nor does the evidence show any long term mass slide of voters toward the right. In short, Reagan was elected primarily because he is not Carter, as Carter was voted for because he is not Reagan. Reagan, for all his campaign posturing, says he thinks "I'm kind of moderate."

He has surrounded himself with middling administrators from the Nixon and Ford administrations; there is not one certified red-hot radical rightist among them. He has been backing away from the libertarian theoreticians in the party for a good while.

Jesse Helms found the radical 1980 Republican platform a good one. Reagan's man Ed Meese quickly noted that "a platform represents the party. A presidential candidate represents his own policies and views." Since the election, the news has been thick with the oil of compromise, as the edgier campaign statements are reinterpreted into moderation.

Reagan's old friend, Tom Reed, says that for Reagan, "The reasonable periods come when he is in office." That was the case, at least comparatively, when he went from 33 years of show business into the California governorship. As is now well known, his record in office bore only a near-random relationship to his rhetoric in running for it.

Reagan never signed on with Ayn Rand or any other intellectual; his conservatism is an attitude, not a theory. Not even his litany of values -- "family, work, neighborhood, freedom, peace" -- connects clearly with either his personal or his public priorities.

He speculates that "maybe the people see themselves and that I'm one of them," but of course his round of life has been unplugged from that of mainstream America.

Reagan's operative world view -- the one he acts upon -- seems clearer. He is a Republican millionaire and hangs around with those folks. Like them, he values "success;" like them, he has not much respect for the regular arts of politics.

He was drafted for the gubernatorial race by the group of rich, aging Californians who then became his friends, managing his trust, counseling him regularly.

Twentieth Century-Fox bought 236 acres of his for "nearly 30 times what he had paid for it only a few years before and twice what it was appraised at by Los Angeles County," according to Atlantic magazine. In 1974, nothing having been done with the land, it was sold to the state of California for about one-fifth of the original price.

The deal still waits explanation. What is clear on the record, though, is that Reagan's administration was, as he put it, "business oriented." During his administration, ruling after ruling paved the way for big gains by private corporations. Reagan would not release his income-tax returns, except for 1970 when, his aide said, he owed no tax.

A reasonable inference is that as long as Reagan's business friends are happy with moderation, he will be, too. He is unlikely to go off the deep end with Milton Friedman; already he has allowed that the Chyrsler bailout is okay after all, and the New York City bailout and farm parity and maybe even the minumum wage and involutary social security.

His domestic economic policies may indeed turn out to be too watered down to be effective, whatever their supposed ideological base. The foreign policy his business friends will press on him cannot be inferred from his California experience.

A reasonable guess would be: distract attention by waving the fist at the Soviet Union, while quieter and more profitable arrangements are worked out "realistically" in the Third World, unhampered by "Utopian" human rights considerations. As president, Reagan is as likely to be "business oriented" as ever, at home and abroad.

What makes it difficult to sort out Reagan's operative world view is his peculiar way with rhetoric. Obviously, it dominates his political style.

Reagan has little interest in homework on the issues; he gets his staff to reduce the information to one page per problem and usually takes the staff's recommendation. The charms of personal negotiation are also lost on him, particularly if they involve an element of disagreement or confrontation. The staff takes care of that, too.

Reagan himself is in charge of the speaking, composing from bits and pieces of information he discovers. His rhetorical output has been enormous. In 1960 alone, he gave about 200 speeches as a Democrat for Nixon.

The Carter-Mondale campaign collected a sizable pile of notebooks filled with Reagan's most egregious bloopers -- not only outrageous recommendations, but also gross factual errors about important issues.

To Carter, these books proved Reagan "ridiculous," a man out of touch with the simplest realities of political life. To Reagan, they were just blown lines to be done again or passed over. He described his method of speech research: "Like any other speaker, I'd see something, and I'd say, 'Hey, that's great,' and use it."

The content of his speeches is for effect, composed to elicit a response from the audience at hand. Reagan often goes overboard when he adds some thrilling assertion for the audience present. But his style of speaking is far more closely studied -- he has spent hours perfecting a toss of the head, a shrug of the shoulders, a crease of the brow. Reagan, after all, came to political rhetoric from acting, and acting reinforced his natural ability to pretend.

I think he experiences most of his own political speeches as if they were fiction.As a young boy, Reagan was extremely nearsighted and had to bluff his lessons in school. More pretending was necessary to hush up and conjure away from reality his father's drunkenness.

More again to play football without much weight and height and more to get through college exams without studying the material. He got his first radio job by demonstrating he could pretend to be watching what he was only imagining -- a mythical football game. He went on to become expert in faking live broadcasts of ball games from wire-service reports.

His theatrical experience began long before that, at home listening to mother and dad declaim classic plays, then taking part. When suddenly Ronald began to read at age five, his surprised mother at once got the neighbors in to listen to him perform.

Acting in movies, the most hypnotic of pretend media, simply extended this fictional experience. "So much of our profession is taken up with pretending," he wrote, "with interpretation of never-never roles, that an actor must spend at least half his waking hours in fantasy."

He told his aide Stuart Spencer in 1966 that "politics is just like show business. You have a hell of an opening, coast for a while and then have a hell of a close."

As his brother Neil put it, "Ronnie always played Ronnie." He is a master at playing himself, and he achieved that mastery in its fullest flower in political speechmaking, first for General Electric and then in his own campaigns. He knows the power of narrative and timing and eye contact and even the technique of the apparent stumble.

But he has never given evidence of a mind that links what he says today to what he was yesterday or what he will do tomorrow. His rhetoric is essentially ahistorical and apolitical. He is bound to contribute to the ever-widening gap in American politics between speech and meaning, presaged in the isolation of the campaign from the presidency, preparing the way for the Orwellian absurdities.

Reagan's way of being a politician is held together by his character, his orientation toward his own experience. As Lou Cannon noted, he is "basically a passive person," a conserver of his energies, a take-it-easy type.

And, as everyone everywhere has noticed, he is an optimist, a booster, a smiler, a genial fellow. In my jargon, that combination makes Reagan a "passive-positive," that is, "the receptive, compliant, other-directed character whose life is a search for affection as a reward for being agreeable and cooperative rather than personally assertive."

The good of that is that Reagan is definitely no Nixon; as his party's cochairman Betty Heitman put it, "There is no hatred in him, no vindictiveness, no grudges, no desire to get back at anybody."

The worry of that is his type's tendency to drift, particularly with forces in the close-up environment. The danger is confusion, delay and then impulsiveness. If tragedy comes to Ronald Reagan, it will be because he wants to be liked too much.

There is no great mystery about the roots of Reagan's compliant, genial stance toward life. He was his mother's boy, named after her, appearing when she and his father expected a little girl.

The family tale is that at birth his father said that "For such a little Dutchman, he makes a hell of a lot of noise," but his mother said, "I think he's perfectly wonderful."

His older brother became the outdoor type, bluff and hearty like their father. Ronald, very nearsighted and slight of build, played indoors, with the toys in the attic or "hidden in a corner downstairs in Uncle Jim's jewelry store, with its curious relics, faint lights from the gold and silver and bronze, lulled by the erratic ticking of a dozen clocks and the drone of customers who came in."

His huge black spectacles made him shy, but his mother showed him a way past that. She "had a conviction that everyone loved her just because she loved them."

Always cheery, she taught him not to condemn his father for his drinking, a disease, not a crime. Despite much instability and shifting about, Ronald learned to paper over the unpleasant side of life: "We never had a worry in the world that I can remember."

He learned to accentuate the positive, to smile and encourage and step aside from trouble. People came to like him. Eventually, he found a wife, who, fleeing her own ghosts, clung to him like a ship-wrecked sailor to a floating spar, constantly reinforcing his courage, protecting and advancing him.

"Ronnie is the softest touch in the world," she said. "I'm always sorry when I read he's unfeeling. You know, he's the most sentimental, tender man I've ever known."

Having taken on a sentimental president, now we must live with him. The odds are small that, four years from now, he will emerge pleased at his presidential role. He is a nice guy who finished first, soon to discover that not everyone is a nice guy.

The best hope is that, like Gerald Ford and Jimmy Carter, Ronald Reagan will leave the Constitution about as he found it and the nation at peace. The worst fear is that Reagan, seeking affection, will have disaster thrust upon him.