Washington — The Soviet response to the Reagan administration's toughening of foreign policy has taken on a clearer outline. The two immediate aims of the Kremlin apparently are:
* To explore a new tactic to prevent NATO from deploying Pershing II and cruise missiles, which it has agreed in principle to introduce into the European theater in 1983.
* To take some of the thrust and urgency out of the new administration's drive to boost US and allied defenses by pressing for an early summit meeting between Presidents Reagan and Brezhnev.
The Kremlin's current approach is one of high-pressure sweet reasonableness rather than of threat or bluster. By this means, the Soviets apparently hope to exploit to their advantage to subtle difference between the United States and its European allies when it comes to striking a balance between security and detente. European thinking is inclined to give a higher priority to detente, American thinking to security.
This week's visit to Washington by West German Foreign Minister Hans-Dietrich Genscher was used by the Kremlin to put its policy into high gear.
The Soviets know that the WEst Germans are more sensitive than most other NATO allies to detente, for psychological, georgraphical, and economic reasons. They know that West German Chancellor Helmut Schmidt is under pressure from the left wing of his own party, which argues that tough talk is not necessarily the best way to deal with Moscow. And they know that when West Germany agreed in 1979 to accept Pershing II and cruise missiles on its territory, that agreement was conditional on negotiations in the interim with the Soviet Union on the control of what are called "long-range theater nuclear weapons" -- in other words, of NATO and Warsaw Pact nuclear weapons in Europe.
So, just as Foreign Minister Genscher was heading for Washington, the Kremlin sent off to Western alliance leaders a letter from Soviet President Brezhnev. The full text of these letters has not yet been published. But the tone is known to be conciliatory and (at least in the communication to Washington) to enlarge upon the Soviet leader's proposal before the recent 26th Communist Party Congress in Moscow for a meeting between himself and President Reagan. One of these letters went to Chancellor Schmidt.
But if the Soviet intent was to drive a wedge between West Germany and the US during Genscher's talks here, the Kremlin failed. All outward signs are that Genscher's talks with Reagan and Secretary of State Alexander M. Haig Jr. went standing that the latter developed with allied leaders in Europe while he was supreme commander of NATO in Brussels.
Some West German cutbacks in military spending, announced on the eve of Gencscher's departure for Washington, did not emerge as a divisive issue. Genscher said after the talks that West Germany's military obligations within the alliance "will be implemented."
Most important from West Germany's point of view -- since it will help Schmidt politically at home -- was the pledge of support that Genscher got from Haig for early talks with the Soviets on control of theater nuclear weapons. Haig reaffirmed US acceptance that there are two simultaneous levels to the question of NATO's deploying theater nuclear weapons in Europe: on the one hand, the acceptance and siting of them; on the other, discussions with the Russians about controlling this kind of weaponry on both sides of the line of confrontation between NATO and the Warsaw Pact.
The proposed installation of Pershing II and cruise missiles is intended to offset the Soviet advantage in Europe with SS-20 missiles and bAckfire bombers on its side of the line. Both the US and West Germany pour cold water on Brezhnev's proposal for a moratorium by both sides on further deployment of theater nuclear weapons, because that would stop NATO deployment of Pershing and cruise missiles but leave the Warsaw Pact with its advantage in SS-20s and Backfire bombers.
Haig said at the conclusion of his talks with Genscher that "the problem now is to proceed rapidly, in consultation with our allies," the agree about talks with the Soviets on the resumption of negotiations on the control of theater nuclear weapons.
There is not the same sense of urgency in Washington about either a Reagan-Brezhnev summit or resumption of discussions with the Soviets about strategic arms limitations -- that it, control of intercontinental as opposed to European theater nuclear weapons.