The Soviet Union seems intent on portraying Poland's declaration of full military rule as a purely Polish decision, despite consistent Moscow pressure for a crackdown on the reform movement there.
The Soviets are seen as fearful that the West will brand them as masterminds of what one Washington official reportedly termed a move toward ''head-cracking'' in Poland.
The Warsaw television announcement early Dec. 13 of a state of emergency came as the Kremlin was bidding for improved ties with the West, particularly with Western Europe. The seriousness of this effort has been underscored by an unprecedented Soviet surrender to a protest by dissident physicist Andrei Sakharov.
The government newspaper Izvestia, in a one-paragraph item Dec. 12, confirmed that Moscow had ''exceptionally'' agreed to let Sakharov's daughter-in-law emigrate to the United States - the demand for which he and his wife began a hunger strike last month.
The Warsaw crackdown by Premier Wojciech Jaruzelski - including a number of arrests, a ban on strikes and demonstrations, and creation of a military ''council of national salvation'' - followed a renewed toughening of Soviet news media comment on the Polish situation in recent days.
But in their initial accounts of General Jaruzelski's move, the media here adopted a tone of detachment, reporting the premier's television address and subsequent developments without immediate comment.
Diplomats saw this as an indication the Soviets sought publicly to distance themselves from the Polish action and to portray it as the Poles' own decision. (The expectation is that any Western criticism of the Polish move will be roundly denounced by Moscow as ''interference'' in the Poles' internal affairs.)
Meanwhile, Soviet officials presumably are biting their nails and keeping a close watch on what will happen next inside Poland. This and other foreign correspondents who tried to phone Warsaw Dec. 13 were told that ''the line does not work.'' It seems unlikely President Leonid Brezhnev's brain trust is having the same problem.
There can be little doubt, given what the Soviets have been saying publicly and privately in past months, that the Kremlin welcomes the Polish leadership's new toughness toward its political opponents.
The Soviet press, sooner or later, will likely say so.
The Soviets certainly knew about Jaruzelski's intentions beforehand. This helps explain why the official Soviet media, after a relative lull in doomsday dispatches on the Polish situation, got back in the swing of things Dec. 10 with a report portraying Poland as near the brink of ''antisocialist'' insurrection.
The account, from the news agency Tass, was read out on the evening television news. On Dec. 12, Tass accused ''counterrevolutionary elements'' inside the Solidarity union movement of ''preparing for direct seizure of power.''
All Poland's communist allies, Tass said, supported ''increasing'' calls within Poland to give ''enemies of socialism the rebuff they deserve.''
All this had been said on earlier occasions by the Soviet media, but not for some time, and not quite so explicitly. One senior diplomat commented Dec. 13: ''None of it was radically new. But, admittedly with perfect hindsight, and given what actually was happening inside Poland, I think the recent coverage does reinforce the obvious: that the Soviets both knew and approved of the Jaruzelski announcement.''
But some Soviet officials have indicated privately they see potential dangers as well in the kind of crackdown announced by the Polish leader.
It might not work, for one thing. But worse, it might push Poland into open civil strife and, in turn, force the men in the Kremlin to decide an issue they have long sought to defer: whether or not to intervene militarily.
Since the emergence in summer 1980 of East Europe's first free labor union movement, the Soviets have used just about everything short of a tank assault in their bid to halt Polish reform and to restore some muscle to the country's beleaguered communist leadership.
The tools in the Soviet campaign have included summitry, top-level speeches, trips to Warsaw, military maneuvers, two harshly worded notes promptly leaked by the Poles, and bookfuls of media commentary.
Last spring officials here privately told East Europeans that one option on the Kremlin drawing board was to press the Polish leadership to impose martial law, or to declare some form of national emergency.
Publicly, however, the Soviets did not go that far. Even when Jaruzelski's predecessor as party chief, Stanislaw Kania, openly mentioned the possibility of such steps, the comment was not picked up in the Soviet press.
The omission presumably reflected Soviet awareness of the seriousness and potential dangers of such action. The press did, however, make clear the Kremlin desire for a tougher Polish stand on other specific issues: strikes, opposition access to meeting halls and the mass media, and the like.
That the Soviets (at least) endorsed Jaruzelski's move Dec. 13 seems to have stemmed from the increasingly militant behavior of Polish reformers, and from a Kremlin feeling that Jaruzelski, a widely respected military man, may have a better chance of making a crackdown work than any of his predecessors.