ABOARD AIR INDIA ONE -- When Indira Gandhi was elected prime minister of India for the first time, she wrote a letter to her elder son Rajiv telling him that a line of Robert Frost's had been running through her head: "How hard it is to keep from being king, when it's in you and in the situation."

Four generations of the Nehru-Gandhi family has been the situation of Indian politics. Rajiv Gandhi's great-grandfather Motilal Nehru was a pioneer in the independence movement. Jawaharlal Nehru ruled for 17 years, from the day India won autonomy from Britain in 1947. Nehru's mercurial daughter Indira ruled on and off for 15 years, and her younger son Sanjay was widely considered presumptive heir until he crashed his two-seater plane in 1980 while doing daredevil stunts over Delhi.

Only Rajiv stayed aloof. A child of the postindependence generation, there was no fire in him, no sense of struggle. He wanted to fly and be left alone. While Sanjay flew his plane in somersaults, Rajiv, as a pilot for the country's domestic line, flew ordered commercial routes. Sanjay was impulsive, autocratic, a cunning political animal, his mother's son; Rajiv was cool, shy, so unpolitical that he married an Italian -- a seemingly disastrous move if one were trying for public office in India.

Not until Sanjay died did Indira and her colleagues in the Congress Party cajole Rajiv into politics. And only when two Sikh bodyguards murdered Indira Gandhi three years ago did he assume national importance.

His ascension was a cliche'd turn on the line of Frost's. It was never in him to be king; kingship -- albeit the kingship of the world's biggest democracy -- was thrust upon him.

" 'Reluctant Rajiv'?" Gandhi says, laughing in his jet cabin Sunday morning. He was on his way from Vancouver to Boston, where he was to speak at Harvard, and today he meets with President Reagan at the White House. " 'Reluctant Rajiv?' One of our chaps who does speeches with me loves alliterations. He'll love this!

"But it's no myth. Not only was the picture true then, it's still true. I feel it has not changed. Perhaps others could comment better, but I don't feel that I am changed. Why did I keep away? Because there wasn't a need to be involved. The family was involved. It doesn't mean everyone has to get involved. When my brother died there was a need."

Gandhi's burden is tremendous. His popularity has slumped after three years of rule. He must try to lead, not merely manage, a country of 750 million that will, in two decades, pass China in population; a country more divided than ever along religious, linguistic and caste lines; one more fundamentalist, more violent than it has been in years.

In the last four months alone 550 Sikhs have died in fighting with Indian forces. To be prime minister of India may be the most difficult administrative job in the world. Gandhi is learning on the job. "Not only can India be led," he says grimly, "India can lead."

And yet, as he talks about his prepolitical youth, he seems so ordinary, young and privileged, comfortable wearing pressed jeans and a gold watch, happy to be talking about pleasures rather than Sikh violence in Punjab or war in Sri Lanka and Fiji. He seems chatty, facile, relaxed, stunningly plain. Before his ascension in politics, his biggest ambition was to move up from Indian Airlines' propeller planes to Boeing jets.

"I came back from college and started flying in 1968. I loved it. I'd done some gliding before, and I just enjoyed it. Flying was like a holiday.

"On the airline, I was on first-name terms with everybody. And because I was on first-name terms with everybody they started putting my name on the roster as Rajiv, as opposed to Gandhi, and it just stuck from that. I never announced my name at all when I made announcements. I would just say, 'This is your captain speaking.' "

Reluctant Rajiv. At Cambridge University, fellow students would ask if he was related to Mohandas Gandhi, the leader of the nonviolent independence movement. He would merely say, "No, I'm not," never explaining that the movement's other great leader was Nehru, his grandfather. "And it was worse than that," Gandhi says. "My grandfather visited school while I was there, and I just disappeared. They couldn't find me. I was staying away from publicity and the limelight. I couldn't stand being photographed when . . . well, until quite recently, actually. Now I can't avoid it."

Reluctant or not, Rajiv Gandhi has become another major character in the Nehru-Gandhi epic. According to Salman Rushdie, the Indian-born author of "Midnight's Children," a novel describing Rajiv's postindependence generation, "The story of the Nehrus and Gandhis has provided more engrossing material than anything in the cinemas or on television: a real dynasty better than 'Dynasty,' a Delhi to rival 'Dallas.' "

Not only has the saga included three generations of political power but countless episodes rich with intrigue and gossip: the tension and distance between Rajiv and Sanjay; Sanjay's wife Maneka's attempt to defeat her in-laws; the tragedies of Sanjay's crash and Indira's assassination; Rajiv's marriage to a European who had to learn to wear a sari and speak Hindi; and now the spectacle of Rajiv's principal opposition coming from a cousin and former ally, Arun Nehru.

"The continuing saga of the Nehru family, of the vicissitudes of Jawaharlal, Indira, Sanjay and Rajiv has been, for hundreds of millions of us, an obsession spanning more than three decades," Rushdie writes. "We have poured ourselves into this story, inventing its characters, then ripping them up and re-inventing them. In our inexhaustible speculations lies one source of their power over us. We became addicted to these speculations, and they, unsurprisingly, took advantage of our addiction. Or: we dreamed them, so intensely that they came to life. And now, as the dream decays, we cannot quite bring ourselves to leave it, to awake."

In June 1984, Indira Gandhi sent her army into the Golden Temple of Amritsar to crush a group of Sikh extremists led by Sant Jarnail Singh Bhindranwale. Four months later, on a late October morning, Indira Gandhi was walking in the garden of her home and office compound. She was not wearing the bulletproof vest she usually wore under her sari. Two of her security guards, Sikhs named Beant Singh and Satwant Singh, cornered her and shot her dead.

For hours, members of the leadership denied or failed to confront the assassination publicly. Even while President Reagan announced his condolences, the official news media, according to Indian journalist M.J. Akbar, persisted in telling the country that Indira Gandhi was wounded but alive in the hospital.

Rajiv, by now a member of parliament, was campaigning that day in West Bengal. He was handed a note saying that there had been an accident involving his mother. Calmly -- all the reports seem to insist on that word, calmly -- Rajiv Gandhi, Reluctant Rajiv, whose wife Sonia once said that she would rather see their two children begging in the streets than see her husband get into politics, flew back to Delhi, and, at the age of 40, became the prime minister.

Now, three years later, he lives a life insulated by guards and barriers. Radical Sikhs have sworn their revenge. There are no longer any Sikh bodyguards in the house of Gandhi. His house and office compound are surrounded by blockades. The trees are stuffed with floodlights and cameras. His teen-age son and daughter cannot go to school; tutors visit them. The street they live on in New Delhi is sealed off. His wife suffers from the isolation. When Gandhi travels to the countryside to meet with village people, the meetings are, by necessity, sanitized, which cannot help at a time when he is increasingly unpopular.

At the airport in Vancouver, the press corps assembled in a cold, cavernous hangar nearly three hours before takeoff. There were endless security checks: X-ray, then dogs, then a hand check of all luggage, then a body search.

In his cabin, Gandhi makes light of it all: "I don't know that it's any more than for any other heads {of state}, like your own president or European heads. In the city, in Delhi, it's slightly more inconvenient for people because they have to go through security checks and things like that. Metal detectors and whatnot. But when I go out of Delhi, I just stop and talk to people wherever I want to."

Journalists who cover Gandhi say this is just not so, that towns and villages are painstakingly checked before any kind of visit.

"For the family it's been very difficult," Gandhi says. "Going to school, getting roughed up, mixing with other kids and mixing with a limited group of children, well, yes, there's a lot of difference, yes."

Asked if he worries about his own safety, Gandhi laughs a laugh that rings of rehearsal and denial: "For my personal security? No. Not at all. It's not my problem. It's the problem of the people who look after it.

"I try to be good with the security and not put them out of line, so to say. But I don't let it interfere with what I'm doing. So far I've found that, except for a very few occasions, they've been very cooperative and we've found a solution instead of a block."

A year ago Karamajit Singh, a 26-year-old man from Punjab, tried to shoot Gandhi with a crude pistol as the Indian leader was leaving a memorial to Mohandas Gandhi in Delhi. Six people were injured.

In Colombo last July, a member of the Sri Lankan Navy honor guard swung his rifle at Gandhi, hitting him on the head and shoulder. Gandhi was not seriously injured.

As his mother did, Rajiv Gandhi wears a bulletproof vest in public.

"Rajiv is in definite peril and he knows it," says V.N. Narayanan, editor in chief of the Tribune of Chandigarh. "He cannot trust a Sikh. I think that if he dies in his bed, it will have to be as prime minister. That's the only way to get the protection he needs."

Indira Gandhi gave birth to a son on Aug. 20, 1944. Later she would describe the experience in rather casual terms: "I just felt hungry and asked for a piece of toast. As I was eating, Rajiv came out. I was so sorry I couldn't finish my toast."

Rajiv's childhood was princely. He and Sanjay were in the care of a Danish governess and attended the Doon School in the Himalayan foothills, a kind of Indian Eton or Andover. As a boy Rajiv visited Mohandas Gandhi. He laid chains of flowers at the mahatma's feet. The next day a Hindu extremist shot Gandhi dead. Indira Gandhi was the dominant figure of his youth. Gandhi's father Feroze, who was a member of parliament, died of a heart attack 26 years ago.

According to Tariq Ali, author of "An Indian Dynasty," Rajiv Gandhi did not completely ignore politics during his years as a pilot, or as a student of mechanical engineering in England. Like his peers he was a liberal-democratic supporter of the Congress Party. "Nonetheless he and Sonia were totally opposed to his entering the cockpit of Indian politics," Ali writes. "She, probably much more than he, regarded politics as filthy, corrupt and riddled with sycophants, whom she disliked intensely."

Indeed, his marriage to Sonia Maino, the daughter of an Italian businessman, was an act of political denial as well as love. At first even his mother opposed the match. "India is a very traditional society," Gandhi says now, "and there are these deep-rooted feelings on certain things. I don't think my marriage is one of those. People are trying to make it so for political reasons, but I don't think it is there amongst the people. My wife goes out to villages and very traditional homes and there is no problem.

Narayanan disagrees: "No problem? Millions still are troubled by that marriage."

Though he denies the story, many Indians say that as a young man Rajiv once told his mother that he and Sonia wanted to settle, at least temporarily, in Italy. Indira implored them to stay, and they did.

For a year or two after he was appointed prime minister and then won the office with a landslide electoral victory, Gandhi enjoyed a political honeymoon. Not only did he have the sympathy of the people, he also encouraged their confidence by preaching the gospel of computers, technology, nonalignment. He threw out scores of sycophantic Congress leaders and replaced them with younger, untainted advisers, many of them friends from the Doon School.

But now the honeymoon is over.

Political rivals have denounced the government for corruption, an inability to find a political settlement for the Sikhs in Punjab. He gets flak from abroad, as well. Yesterday,a U.S. congressional report accused Gandhi of dealing with the Punjab with an "iron fist."

His organizational skills have been questioned. In the past couple of years, Gandhi has fired or lost some of his most trusted young advisers, one of whom is his cousin Arun Nehru. Now Arun Nehru is supporting one of Gandhi's strongest rivals, V.P. Singh. Singh accuses Gandhi's government of accepting $50 million in kickbacks from a Swedish weapons firm. Gandhi says the contracting scandal will not implicate him or any other Indians.

More and more Gandhi is a man of the party rather than a creature of his mandate. If he were to call an election today he would probably win, but not by much, according to several Indian journalists.

"I tried at the beginning for about a year to carry all the groups with us," he says. "But I found you couldn't get things done if you tried to carry all the groups with you. After all, India elected the Congress Party, and we're not being fair to the people if they're giving us an 80 percent majority in Parliament and then we go and dilute our policies on the basis of what a very disparate and very divided 20 percent think.

"Also, I found that the opposition was seldom coming out with concrete guidance on policy. Even today, if I call together opposition leaders -- and I called them last week before coming to Vancouver -- and ask for ideas on the Punjab, ideas on the economy, well, they have no ideas at all! It's all negative. Like, 'What do you want to do, then we'll comment.' They haven't thought it through. The biggest problem with our opposition parties is that none of them -- and I mean none of them -- have a proper policy framework."

Narayanan, one of the few journalists traveling with Gandhi's party who is critical of the government, praises the prime minister as "a man obsessed with wanting to do good" and "charming one-on-one" -- which he is -- but "Rajiv is not someone who can address the nation like his mother could. Sanjay was more of the soil. Rajiv has the gentle manners of the West. I wouldn't call him an Oriental person. In that way he's more like his grandfather than his mother. But Nehru was a cult figure. Rajiv is not."

In interviews, Gandhi deals with issues with facility and candor, if not great depth. "He's the new generation of leader," says Aroon Purie, editor of India Today. "Rajiv doesn't deal in ideology. He's at the step of trying to make things work."

On a Separate Sikh State: "Absolutely no possibility. And there is absolutely no question of compromise with terrorism. We are going to face it head on and finish it. We are willing to talk to anybody -- and I mean anybody -- who will talk within the framework of our constitution and is willing to give up violence."

On increasing violence: "On the one hand, it is part of a global trend. There has been a rise of fundamentalist attitudes right across the world. Even in the United States there is a very strong right-wing Christian movement. There is also a worldwide trend toward violence, because weapons, sophisticated weapons, are available much easier and at much lower cost than they were earlier.

"Having said that, it doesn't reduce our responsibility to handle it at home. We must do so, and we will do so. I believe the problem is not just a superficial problem of a few people going berserk. It is a much deeper rooted problem. It is part of the development process, the trauma that our society has to go through when we try to condense a couple of centuries of backwardness, perhaps in some areas much more than that, into four decades."

On Indo-American relations: "There is a very strong link. The link is many shared values: democratic, on human rights, it's a vast thing. The differences are because we see things from our point of view. You see things from your point of view. You are a major industrial power, a major military power, you have your own perceptions. We are a developing country, sensitive to economic shifts, sensitive on our independence because we won it with great difficulty . . .

"But while the U.S. stands for everything we feel is right -- and there is very little we disagree with -- the U.S. supports countries which contradict everything the U.S. stands for. As in South Africa. When it comes to support, the U.S. is willing to give greater preference to its great-power needs or spheres of influence or bloc divisions than to the basic tenets on which it was formed."

On why he will not sign a nuclear proliferation treaty: "It's blatantly unfair. First of all, it's blatantly unfair in the way it treats the non-nuclear-weapon countries and the nuclear weapon countries. Secondly the nuclear weapon countries are not adhering to the NPT although they've signed it.

"We have demonstrated that we have the capability to build a weapon but we have not built a weapon. No other country has done that. We believe that nuclear weapons are dangerous. They do not lead to peace, and they will lead to catastrophic consequences."

On the friendliness of Indo-Soviet relations: "The message we're trying to get at is that you can have different systems. To us democracy means allowing people to have their own systems. So long as the system doesn't violate basic things of human rights. Like South Africa. Apartheid is abhorrent, so you can't allow that. But when you pull back from that limit you should allow societies to function their own way. If you want to win them over to your way of thinking, then you must win them over, not fight them or bully them or coerce them into it. That's what peaceful coexistence is all about.

"It's the level of freedom. There is no racial discrimination in the Soviet Union."

It is widely assumed in India that Rajiv Gandhi will be the end of the dynasty. But Gandhi leaves the question vague. "I don't think my grandfather or my mother, in their turn, wanted anything -- not my grandfather for my mother or my mother for us. I don't want anything for my children except for them to decide for themselves what to do and grow up as normal human beings. If at some later date they want to go into politics, I'm not going to stop them, either dissuade or persuade.

"In India we inherited a feudal society. That is changing. It has changed tremendously already. It's a process which takes time. You can't switch off feudalism or a feudal attitude. You have to wear it out, break it down. You have to win over the people.

"I have tremendous faith in our people. They may be illiterate, they may be uneducated, and perhaps because they are uneducated they have a deep wisdom. And that wisdom, together with the strong democratic roots that have been forged during these 40 years, will give India the stability it requires. It does not need a Gandhi or a Nehru."

Salman Rushdie sees the family as a persistent "collective dream," and in it, "Jawaharlal Nehru represents the dream's noblest part, its most idealistic phase. Indira Gandhi, always the pragmatist, often unscrupulously so, becomes a figure of decline, and brutal Sanjay is a further debasement of the currency. It's hard to say, as yet, what Rajiv Gandhi stands for in this analysis. Perhaps he is the moment before the awakening, after all ... In India today, the sounds of reality are insistent and harsh. Rajiv may not be enough of a sandman to keep the people asleep."

He was not a leader by choice, yet now he wants to stay on. "I'd have been very happy in the airline. We used to fly two days a week. It paid for relaxing five days a week. You miss it in the sense of, yes, well, it was great. But the challenge of today draws you out and makes you more interesting and exciting."

The plane lands at Boston's Logan International, and through the window Gandhi sees security guards on the hangar roofs. They are holding submachine guns. Gandhi barely has time to change into a Nehru jacket, shake some hands and wave before he steps into a car and is gone.

Were it not for the tugs of power and family, Gandhi might be somewhere else now, unthreatened, just himself, flying into the blue. "There are still places you can find where nobody can get to you," he says. But not for him. Not anymore.