Chernenko returns to a complex world.

Chancellor Helmut Kohl is trying to limit the damage to East-West relations that might flow from the indefinite postponement of East German President Erich Honecker's first visit to West Germany.

Dr. Kohl is still counting on receiving the Romanian and Bulgarian heads of state in his capital this month and next as part of his contining effort to keep the East-West dialogue going below the superpower level.

In a sense, Kohl is acting as advance man for the rest of the members of the European Community. They have all taken care to keep open their lines to Moscow despite the collapse of Soviet-American talks on strategic arms in December.

As Kohl sees it, his activities disprove warnings that deployment last year of American Pershing II missiles in West Germany would trigger a diplomatic ''ice age.''

Mr. Honecker's decision to cancel the Sept. 26-29 dates he had himself proposed for his first visit to West Germany is seen by Kohl's government as no impediment to continued negotiation at working level.

As proof, the government cites the fact that even after Ewald Moldt, Honecker's plenipotentiary in Bonn, announced the postponement of the September visit, he then sat down for a review of the joint communique to be issued when the East German Communist chief does finally make the trip.

Kohl said recently that the German states are conducting 17 different negotiations simultaneously, many of them involving proposed joint action to clean up the environment. Both sides apparently intend to keep these going despite the delay in Honecker's visit.

As West Germany and East Germany are the European ''frontline states,'' respectively, of the American and Soviet-led political, economic, and military alliances, they are more affected than others when relations between the two superpowers worsen.

After the Soviet invasion of Afghanistan, Helmut Schmidt, the Social Democrat who was then West German chancellor, went to Moscow in an attempt, as he put it, to at least keep a dialogue going in Europe - to save what could be saved.

Christian Democrat Kohl, who at that time was critical of Schmidt, has now adopted a similar policy, making special efforts to keep the lines to Moscow and its satellites open even though the circuits linking the American and Soviet capitals seem temporarily out of order.

In line with this policy, the Kohl government also encourages further development of trade with the Soviet bloc, an attitude that already has brought it into some conflict with Washington.

Martin Bangemann, Kohl's new minister for economics, warned recently that if necessary he would submit legislation to make it impossible for American companies to order their German subsidiaries to abide by US embargoes on exports to the Soviet bloc.

Similarly, although the government accepted the latest additions of certain technologies to NATO's list of items that cannot be exported to the Soviet bloc, the schedule has been widely criticized both by nominal supporters of Kohl's government and by his opponents.

But Kohl's main aim in keeping talks with Honecker's government going is to maintain the unity of the German people.

He says that reunification of the nation is the government's long-term goal. Until then, Kohl says, the Bonn government must do all in its power to ease communist restrictions on the 17 million Germans living under their regime, and to increase human contacts between the Germans in the two halves of the country.

This is why Kohl was willing to have his government guarantee two commercial bank loans totaling about $675 million to East Germany, because in return the communists agreed to permit more and longer individual visits across the demarcation line.

Honecker also ordered dismantling of all of the booby-trapped scatter-guns that guard several hundred miles of the East-West German border to prevent anyone leaving East Germany without permission.

West German officials say that so far about half of the scatter-guns have been removed. Nevertheless, two young men suffered serious shrapnel wounds and cuts when they triggered some of them while crossing from East Germany into Bavaria Tuesday night.