Genscher travels to Moscow to keep East-West lines open

West German Foreign Minister Hans-Dietrich Genscher's visit to Moscow April 2 -4 keeps East-West communications open in a diplomatically fluid period. That is the trip's main function.

There is no expectation that Soviet President Leonid Brezhnev will use the visit --the first by a ranking Western statesman since Ronald Reagan's inauguration and since the tense Polish confrontations of December and March -- to advance new positions on arms control. Nor is it expected that Brezhnev will use the visit to try to woo Bonn away from Washington.

This is the picture drawn by senior Western diplomats in Bonn. It contrasts notably with the last major Soviet-West German get-together, Chancellor Helmut Schmidt's visit to Moscow last summer. Then the Kremlin used the West German visit both to advance arms control as a whole -- by dropping the negotiating precondition of NATO abandonment of 1980s nuclear plans -- and to preen friendly Soviet-West German relations at a time of bad Soviet-American relations.

This time Mr. Genscher's low-key, working visit should serve mainly to bring home to the Russians Western unity and seriousness about arms control. Genscher is expected to explain that if the Soviets continue their propaganda appeal to pacifist West European public opinion over the heads of West European governments, they will only lose critical time for arms control. He is also expected to stress that any Soviet military intervention in Poland would have the gravest consequences for East-West relations.

These themes are not new. But they bear repeating in a confused period in which the new administration of a hospitalized American president has not yet really defined the specifics of its East-West policy -- and a period in which Poland remains a tinderbox.

Mr. Genscher's trip comes at a time when Soviet-West German relations are somewhat reserved. Moscow, of course, hangs on to the option of trying to pry Bonn away from Washington, but since last August it has clearly subordinated this tactic to the higher priority of holding over Poland a threat of Soviet intervention. The two policies are obviously incompatible.

The result is ambivalence in Soviet policy toward West Germany. Bonn was given friendly mention at the February party congress in Moscow (if not as friendly as that accorded France.) Yet the Soviet media have resumed personal attacks on Mr. Genscher (suspended during the fortnight preceding his visit) for joining the other NATO allies in rejecting Brezhnev's February proposal of a moratorium on medium-range missile deployment in Europe.

The KGB seems to be behind the circulation of slanderous anti-West German tracts in Bydgoszcz elsewhere in Poland, in an apparent move to set up a West German scapegoat for any future Soviet invasion of Poland, on the pattern of Czechoslovakia in 1968. The Soviet Union is appealing over the head of the Bonn government for popular renunciation of NATO nuclear weapons --while simultaneously declining to give any diplomatic elaboration whatever to Brezhnev's vague moratorium and other proposals. And the emigration of ethnic Germans from the Soviet Union to West Germany has dropped substantially since last summer.

Genscher's visit is not expected to elicit any improvement in bilateral relations. Nor is it expected to persuade the Kremlin that Moscow must deal seriously with the Western Europe and American governments if it really wants to prevent a new arms race, and not just address Western publics. It is hoped, however, that Genscher's presentation might help speed up Kremlin realization of today's stark nuclear and political realities.