DURING the first two years of his rule, Mikhail Gorbachev has presided over the most profound changes in the Politburo in Soviet history. Measured in quantitative terms alone, only in the tumultuous final years of the Khrushchev leadership was there greater change.
The period 1957-63 is important in Soviet political history for two reasons. First, in 1957, the ``anti-party group'' in the Politburo unsuccessfully challenged Nikita Khrushchev and tried to remove him from office. Fighting to retain his post and to make important changes, between 1957 and 1963 Khrushchev made wholesale changes in the Politburo membership, with an average annual turnover of 31 percent - i.e., the number removed plus the number of new members. (Percentage changes are used here for comparisons, because the number of Politburo members is not fixed and its size varies considerably, even from year to year. In recent years the norm has been some 13 or 14 members.)
Not even during the period when Stalin consolidated his power (1926-38), at the height of the purges, was the annual rate of membership change (24 percent) as high as it was during Khrushchev's final years. For example, for all reasons, including death and retirement because of health, during the placid Brezhnev era the average rate of annual change in Politburo membership was only 13 percent.
In contrast, under Mr. Gorbachev (1985-87) the average rate of annual change has been 26 percent nearly as high as during the Khrushchev upheavals.
A second reason for the importance of the 1957-63 Khrushchev years to Kremlin-watchers is the striking parallel between the reforms Gorbachev is attempting to introduce and the reforms that Khrushchev failed to introduce, which contributed to his downfall. Like Gorbachev, Khrushchev wanted decentralization, and he saw the entrenched party-state bureaucracy from the top to the bottom as a principal source of opposition to major change.
Unlike democracies, major changes in the Soviet Union must come from the top down. Thus, while media attention has been focused on his call for glasnost (openness) and perestroika (restructuring), Gorbachev has been using every opportunity to effect a revolution in the Politburo membership, now nearly complete.
Although the average age of the membership has declined somewhat, the decline has not been dramatic. Thus, whereas the average age of the Andropov-Chernenko Politburo (1982-84) was 67, the average age of the 1987 Gorbachev Politburo is 63 and should rise in the future, given the fact that he now has most of his men in place. Indeed, the average age of the eight new members is 60 and of the candidate members is 62.
Of the six candidate members, four are Gorbachev appointees, including Dmitri Yazov, a relatively obscure general who replaced Sergei Sokolov as defense minister last month when the latter was fired after Mathias Rust's dramatic flight into Red Square.
Beyond the very important fact that of the 13 full voting members besides Gorbachev, two-thirds have been appointed during his tenure as general secretary is the fact that three-fourths have had experience as party secretaries in key republics, regions, or cities.
Although Gorbachev is the youngest member (56), only two other members have served as full voting members longer than he has, Vladimir Shcherbitsky (69), the first secretary of the Ukrainian party, and the aging Andrei Gromyko (78), whom Gorbachev surely neutralized by kicking upstairs to the largely ceremonial position of president; that is, chairman of the presidium of the Supreme Soviet. Immediately after gaining the general secretaryship in 1985, Gorbachev removed Grigory Romanov, who had been his chief rival for the post. Subsequently, four other members of the early 1985 Politburo were removed or retired, climaxed by the 1987 firing of the Kazakh Dinmukhamed Kunayev for corruption and (even more important, I believe) failing to strongly support restructuring. Certainly, those who were removed have been the core of any nascent ``anti-party group'' in Gorbachev's Politburo.
Also, since 1985 eight new members have been added. Last month's changes (including Mr. Kunayev's ouster) have probably completed Gorbachev's revolution at the top. Indeed, the three new members added in June are known to strongly support glasnost and perestroika. Another change in the quality of the membership may be even more important.
Alexander Yakovlev, named early this year to candidate and then in June to full voting Politburo membership, exemplifies the profound qualitative changes made by Gorbachev in less than three years. Mr. Yakovlev, who is a doctor of history, studied as an exchange graduate student at Columbia University in 1959, traveled widely, and served as Soviet ambassador to Canada from 1983 to 1985. As a member of the Central Committee's Secretariat, he is in charge of propaganda. Next to Gorbachev, he has the greatest responsibility for selling the party and the system to the nation and the world.
As important as Gorbachev's having gained a clear majority of the Politburo votes, at least for the time being, is the fact that his recruits are better educated than their predecessors. Does his major change in the makeup of the Politburo mean that in the next few years the significant social and economic changes he has called for will be realized?
History may never repeat itself, but it does offer its lessons. Surely the changes at the top are even more substantive than those achieved by Khrushchev. Yet, the very Politburo that he put together to help defeat the ``anti-party group'' after 1957 turned against him a few years later, joined hands with the entrenched party-state bureaucracy, and forced him to resign. More than anyone else, Gorbachev must be aware of that chapter in Soviet history.
Roy D. Laird is a professor of political science and Soviet and East European studies at the University of Kansas. He is the author of ``The Politburo: Demographic Trends, Gorbachev, and the Future'' (Westview).