For a few hours Monday afternoon, Nikita Khrushchev seemed dead. The Pacific Coast Stock Exchange reacted to the news with a flurry of activity and closed registering a loss. The White House announced tersely that the President was following the situation. Newspapers and television networks pressed their Moscow correspondents frantically for details.

At the State Department, elaborate contingency plans were taken from the files for the information of the President and his advisers. In universities and newspapers across the country, journalists and professors began to ponder what the death meant. If it was assassination, who would be blamed? The Americans, the Chinese, or a deranged citizen? Who had actually killed him? Even if it had been a heart attack--and after the Premier's recent activity in Eastern Europe this seemed possible--the big question still remained. What would happen?

As it turned out, Khrushchev wasn't dead. But the old man is seventy, active, corpulent and subject to fits of peasant anger. He pushes hard with a heavy schedule of travel and speeches, and his forty-seven years in Soviet politics make Franklin Roosevelt's harrowing public years seem lush. The reports of the Soviet leader's death may be true next time, perhaps before the world situation has changed substantially. While the sensations of the mock death scene enacted this week remain fresh, it may be worth considering what a world without Khrushchev would be like.

The question of how internal politics would change if the man at the center of the Russian power "onion" succumbed, is the most difficult to answer. Would control over the civilian population loosen to show the good intentions of the new leaders while they engaged in the ruthless struggle for supremacy, or would discipline tighten to avoid disorders?

In the top hierarchy itself, what would the power bases be? Would bureaucrats whose support came from the government structure oppose top Communist Party officials, or would the division be between the politicians and the now powerful "technocrats" who are more interested in production than in party patronage? Probably the most serious cleavage in the leadership would be between the old revolutionary Communists, like Mikhail Suslov, and younger men like Dmitry Polyansky. Suslov and his companions lived through the 1917 revolution and fought upward in the Communist ranks with the sense that strengthening the edifice built against such overwhelming odds justified the Stalinist excesses.

Presidium member Polyansky, on the other hand, is only 47 years old. His first memories are not of the revolution, but a peasant family's view of the early Stalin years. He has not experienced the elation of participating in the revolution; he has only seen the hardship and slaughter that followed it. The policies he would pursue if he gained power would certainly, within the limits of rational interest, be different.

What would the Soviet Union attempt in foreign affairs in the months after Khrushchev's death? Only one prediction is fairly safe: the leadership would seek to continue the detente with the West and make a show, for the moment, of unity with the Communist Chinese. This was the policy of the collegium in Russia from March 1953 into the summer months--in order to let the leaders concentrate on the power fight.

But such a detente would not prevent international issues, as well as the inevitable internal questions such as consumer goods versus heavy industry, from becoming ideological weapons with which the opponents could assault each other. Traditionally, the victor has been the advocate of a conservative hard line, the position from which Stalin defeated Trotsky and Khrushchev upset Malenkov. But would a hard-line candidate attempt to oust an opponent by breaking the nuclear test-ban treaty or, ultimately, starting a nuclear war to prove that Communist civilization could be built on the rubble of the old order? It is more likely that, following Khrushchev's example, the hard liner would only talk about it.

The question it would be most fruitful for Americans to argue is what the U.S. reaction to Khrushchev's death should be. Should the message of condolences be warm or formal? Much more important, should we adopt an activist policy of profiting from the Soviet disadvantage or stay aloof from the entire affair?

Inevitably there will be a division of sentiment at the State Department. Some officials are reportedly grimly determined to "take advantage" of an opportunity they feel was missed at Stalin's death. Others will argue that such tactics would infuriate the Soviet leadership and end the current detente.

Perhaps the best policy would be a mixture of the two alternatives. It would be insane to announce our intention to free East Germany, but the relaxation of tensions which would probably follow Khrushchev's death might offer a real opportunity to strengthen U.S. economic and cultural ties with the nations of Eastern Europe.

In the realm of hard diplomacy the United States might negotiate for guarantees against aggression: security for West Berlin or an agreement (if one does not already exist) that Soviet toops will not return to Cuba. We might even request that the USSR pay its bill at the United Nations.

These are not offensive policies; in the end they might strengthen the peace that Khrushchev and Kennedy achieved together. They are, on the other hand, valid foreign policy objectives for the United States which the Soviets could meet without loss of face.