Precisely why and how Konstantin Chernenko was selected to succeed Yuri Andropov as Soviet leader is still a mystery. When the choice was announced on Feb. 13, 1984, it came as a shock to much of the nation.

The next day a physically exhausted Chernenko faced the nation from atop the Lenin Mausoleum, presiding over the funeral rites for his predecessor.

First impressions often jell into lasting images, and in Chernenko's case, these were devastatingly negative. As the Spassy Tower chimes signaled noon and the new leader seemed not quite sure how to proceed, the voice of veteran Foreign Minister Andrei Gromyko was clearly heard over the loudspeakers. "Don't take off your hat," he said, turning toward Chernenko.

The new leader looked to his left, got an approving nod from Politburo member Viktor Grishin, and began to read his speech. One could see his breath in the freezing cold of Red Square. It was the shallow breath of a man with a lung problem. His voice lacked firmness. He slurred his words, and one often could not make out where his sentences began and where they ended.

The next speaker was Gromyko, whose eulogy was a masterpiece. He seemed to deeply mourn the dead leader, as did the next speaker, veteran Defense Minister Dmitri Ustinov.

It was the specter of these two powerful figures who spoke forcefully and appeared physically far more vigorous than Chernenko, although he was a few years younger than they, that made the new leader appear a feeble and indecisive old man surrounded by powerful party barons.

It is difficult to overestimate the importance of style and instincts a general secretary of the Soviet Communist Party brings with him to the office. The office itself is not only the vital center of action in the entire system; in a strictly hierarchical political setup, it is everything.

These early impressions of Chernenko, however, turned out in some ways to be unjustified. Less than a year after taking over, for example, Chernenko almost single-handedly engineered a crucial shift in Soviet policy toward the United States. He brought Moscow back to the nuclear arms negotiations at Geneva that Andropov had ordered Soviet delegates to walk out on late in 1983.

It would be difficult to imagine a truly indecisive and feeble man rising to membership in the Soviet Politburo, let alone aspiring to become the country's leader.

For nearly three decades Chernenko had served as the most intimate aide to Leonid Brezhnev, who led the country for 18 years. He knew all the secrets and saw all the papers before they came to Brezhnev's desk. During Brezhnev's last, ailing years, it was Chernenko who in effect ran the country in his mentor's name.

Persons who knew Chernenko described him as a man of above-average intelligence with a talent for organization and a mastery of technical details. Even his detractors concede that he was an efficient administrator. They liked to deal with him more than any other member of Brezhnev's entourage.

Yet his mind, for all its clarity, was conventional, in the traditional mold of a successful party bureaucrat. He was, as one senior Soviet official put it privately, "a tremendously average man" who had risen too high. What propelled him forward also held him back once he assumed supreme power. He was a prisoner of his background as he shared Brezhnev's ideas, style and approach.

Chernenko also inherited Brezhnev's constituency and was its unquestionable standard-bearer in the Kremlin councils after Brezhnev's death.

The most likely explanation for Chernenko's elevation to the top job was that Andropov, during his brief tenure, had shaken up the country to such an extent that the party bureaucracy may have had second thoughts about whether they really wanted so strong and forceful a figure and so disturbing a challenge to the certainty of their existence. For most of them, this theory holds, Andropov's challenge seemed too exacting, and they yearned to fall back to the familiar, safe Chernenko.

Much of the Soviet elite was hoping that the job would go to Mikhail Gorbachev, the youngest Politburo member, who had been obviously groomed for leadership by Andropov.

When the old guard chose Chernenko, it was the lowest point in the protracted transition crisis.

Everything seemed stacked against the new leader. The popular sense of dejection and gloom, which was all-pervasive during the next few weeks, was summed up by a prominent Soviet writer. "I can tell you that as a Russian writer I honestly feel hurt in my national dignity," he said privately at the time. "I love my country, I'm proud of it, I am not a dissident, but I do not want such a man to be at the head of our country."

The sheer contrast of personalities and style worked against Chernenko. Andropov after his death immediately became a Soviet folk hero. Like John F. Kennedy, to whom he otherwise bore no resemblance, Andropov died before one could determine whether he would be able to implement his vision of the country. But in the popular mind he was seen as the leader who would have done what he pledged to do had his health allowed it.

Any Soviet leader would have been at a disadvantage as Andropov's successor. Given Chernenko's public image, his disadvantage was colossal.

Chernenko must have sensed the potency of the Andropov myth. He steered clear of any obvious new departures from Andropov and insisted, at least rhetorically, that he was continuing Andropov's policies. Moreover, he had no program of his own. Andropov had charted the main direction of policy and had brought a number of younger men into the key positions to establish control over his legacy.

The subsequent 13 months were to a large extent a period of truce, a stalemate between the Andropov forces and those associated with Chernenko and Brezhnev.

In the course of these 13 months, Chernenko did nothing to dismantle Andropov's domestic program of economic experimentation. He did not try to stop the anticorruption campaign. It was during his reign that one of his (and Brezhnev's) close friends, former interior minister Nikolai Shchelokov, committed suicide to avoid standing trial on corruption charges.

And yet Chernenko was clearly not the heir and executor of the Andropov legacy. The pace of political life set by the new leader seemed to recall the Brezhnev years and served as a brake on the modernization drive initiated by his predecessor. Andropov's appeals, demanding exertion and sacrifice, were subtly replaced by Chernenko's appeals, promising benefits.

Whether Chernenko wanted to apply the brakes is debatable. "Chernenko," one Soviet official said, "could not slam on the brakes. But he simply took his foot off the accelerator and everything slowed down."

The country, another Soviet analyst said, was "on automatic pilot."

What Chernenko did during his tenure was to calm down sectors of the country shaken by Andropov's presence and to reassure the bureaucracy after a turbulent 15 months. He reversed one of Andropov's last decisions, which called for a drastic cut of nearly 20 percent in the bureaucracy. The plan had been to eliminate a number of jobs dreamed up by officials to take care of their proteges and friends who, in turn, had come to regard their jobs as sacred and unalterable.

Chernenko's other major move was to change Moscow's policy toward Washington on arms control. Back to the Table

Two months before Chernenko's accession, the United States had started deploying new Pershing II and cruise missiles in Western Europe. After a political and propaganda battle that lasted more than three years, the Soviets had suffered a crushing diplomatic defeat, having failed to persuade the Western Europeans not to accept the new weapons.

When the first Pershings arrived in West Germany in November 1983, Andropov ordered his negotiators to leave the Geneva talks. The vitriol of Soviet propaganda soared to new heights.

The walkout was preceded in 1983 by President Reagan's propaganda offensive against the Soviet Union that seemed to reach a new intensity with his "evil empire" speech. Moreover, Reagan had advanced his "Star Wars" program for an antimissile defense shield around the United States. As seen from Moscow, the Americans were breaking all the rules of the nuclear game.

These moves had come in the context of a series of Soviet setbacks and misfortunes among which the Polish labor turmoil stands out. Apart from painful economic and political costs, the Polish crisis produced a crisis of confidence throughout the Soviet empire.

Andropov, who had wanted to concentrate on domestic issues, initially tried to limit the damage. He sought to induce the Americans to negotiate about restraints on the arms race in space while at the same time making efforts to split Western Europe from Washington on the issue of arms control. The shooting down of Korean Airlines Flight 007 on Sept. 1, 1983, finally made it clear to him that the battle for Western European public opinion was lost.

In responding to this disaster, the Soviets appeared to be withdrawing from the international scene. Andropov's statement to the nation of Sept. 27 went so far as to challenge what had been the basic premise of Brezhnev's foreign policy: that detente with the United States was not only desirable but also possible. What Andropov said was that while desirable, detente with the United States was not possible and that confrontation instead seemed inevitable.

It was an angry response.

It was evident that domestic and foreign considerations gave Andropov an almost desperate feeling that he had to do something. Had he not carried out his public threat to break off the Geneva talks once the Americans began deploying new missiles in Europe, he risked a humiliation that would have weakened him at home and made the Reagan administration doubt the firmness of the Kremlin.

Chernenko's attitude was slightly different. Although he did not favor continuation of the Geneva talks under the circumstances, Chernenko felt that the starkly confrontational line was not an adequate response to Reagan's challenge.

Like Brezhnev, Chernenko believed that the equilibrium of force between the United States and the Soviet Union was roughly in balance -- if not in the sense of numerical parity or symmetry of weapons systems, at least in the sense that neither could expect to destroy the other and emerge unscathed.

Like his mentor, Chernenko believed that the overriding need was to prevent direct confrontation between the two nuclear superpowers. In his writings he had been an outspoken advocate of detente, emphasizing the importance of a patient, cool reaction to what he viewed as erratic American behavior.

Although he was not an intellectual, Chernenko had acquired detailed knowledge of nuclear issues and the wisdom that comes with the responsibility entrusted to him first under Brezhnev and subsequently by the party. He felt that the existing power balance could not be changed quickly and decisively, that the Soviet-American arms competition was fundamentally a political conflict, and that Moscow should wait for the end of Reagan's term in the White House.

Moreover, by seizing the initiative in arms control, he could expect to inflict a worldwide political and moral defeat on the United States, or at least put the Reagan administration on the defensive, forced to justify its policies to the American people and their allies.

The change in Moscow's policy evolved speedily. After initial conciliatory noises, Chernenko proposed in late spring of 1984 to open talks in Geneva on space arms in September. When the United States responded that it was willing to talk about space weapons provided that the Soviets return to discuss strategic and medium-range missiles, Moscow branded the reply a rejection of its proposals.

Last fall, however, Chernenko essentially took that American position, turned it into his own, and proposed it to Reagan. Washington had no choice but to accept it and this opened the way for the current Geneva talks. Weakening and Adrift

By all accounts, Chernenko imposed the change almost single-handedly. The speeches of Gromyko and other key policy makers during that period seemed tougher in tone and more unyielding in substance than did Chernenko's pronouncements. One of the victims of this debate was Marshal Nikolai Ogarkov, the Soviet chief of staff and an Andropov loyalist, who was fired unexpectedly in September 1984, before Chernenko advanced his proposals. Ogarkov had been a forceful advocate of military interests, and he now reportedly has been rehabilitated by Gorbachev as commander of Warsaw Pact forces.

But apart from making a personal imprint on foreign policy, Chernenko had done little beyond acting as a caretaker for a new generation of leaders. Many of his public activities seemed confined to ceremonial duties, awards of decorations, pep talks that he found increasingly difficult to deliver.

By the end of 1984, his health began to weaken.

The winter was unusually cold and difficult. A dome of smog and vapor covered the city, making breathing difficult for healthy individuals, let alone for a man suffering from emphysema. He vanished from public view in early January.

In late January rumors began to circulate that Chernenko was dying, and that Politburo members Viktor Grishin or Grigori Romanov were his designated successors.

The prospect of another Red Square funeral -- the third in less than three years -- and another old czar in the Kremlin -- the fourth in three years -- seemed to confound a weary nation. The power transition had been painfully long and demoralizing. It had started in earnest when Brezhnev was hospitalized in March 1982, never to recover fully his former physical and mental vigor. With the exception of Andropov's first four months in office, it had continued without interruption.

At this point a curious, and to many Soviets disturbing, thing happened. With Chernenko hospitalized and fighting for his life, his staff took over, acting in his name. A stream of pronouncements attributed to the leader began to flow from his office.

That Chernenko never saw these pronouncements was made clear in written answers he was supposed to have given to questions advanced by an American television network. Chernenko's answers did not bear his signature at the end, a mandatory procedure in Soviet practice.

"The boys around him, you know, some of them bright, they played games with his speeches and articles, and this should not be done for a leader," a senior Soviet official said privately, speaking about this period.

"They put into his mouth words alien to him. Nobody could stop it, because they were acting on behalf of the leader and you could not reach him, because he was ill. And even if you reached him, you would not want to raise such unpleasant things with a sick man."

The policy drift was almost palpable. So was the despondency of the elite. It was clear that the end was near, but no one knew for sure whether another old man would replace Chernenko.

Ironically, Chernenko's public image changed sharply during the last months of his life. Russians began to look at him in a different way, seeing an old and sick man bravely soldiering on at his post with his patriot's pride in the dignity of his country. He was taken from his sickbed to cast his ballot in an election. Television showed him walking with difficulty, his movements slow and obviously painful, his eyes unfocused, yet struggling to do what was expected of him.

He was again shown on television shortly before his death last March, receiving a delegation and performing his ceremonial duties while suffering pain. And the people began to feel sad and sorry for him.

In contrast to the almost universal rejection that had met his election, Chernenko was accepted by the country in his death.

NEXT: Gorbachev takes over