Suddenly, the relations between Poland's leaders and the Kremlin have plunged to their worst point yet. At the core of the latest crisis is a sharp increase of Soviet pressure on Polish party chief Stanislaw Kania and Prime Minister Wojciech Jaruzelski to turn back the tide of reform.
What is less clear is whether the Soviets are trying to force top-level personnel changes here or, indeed, whether Moscow's new warning to Warsaw represents a threat of invasion or simply another escalation of psychological pressure.
The elements of the crisis include:
* A letter to the 143-member Polish Central Committee (not the ruling Politburo) from the Soviet Central Committee accusing the leaders of the Polish party and government of abdicating to "antisocialist" forces. The letter repeated allegations that the reform movement and Polish leaders had opened the door to "counterrevolution."
* An apparently emergency session of the Polish party Politburo which decided to call a meeting of the Central Committee June 9. One member of the Central Committee described this call as probably the existing Politburo's "last card."
* A postponement of the session of parliament previously scheduled for June 9 to debate various reform measures -- including one to modify the Polish administration somewhat away from the Soviet pattern.
* A speech by Vice-Premier Mieczyslaw Rakowski -- the toughest yet from the government -- warning the Solidarity union movement and Poles at large that (1) the limits of patience for "sensible halfway compromise" had been reached, and ( 2) political pressures and opposition from groups operating inside and outside the union are threatening the foundations of the Polish socialist system and Poland's statehood as well. The patience of Poland's Warsaw Pact allies was running out, he said.
Adding a sinister note, a telex message came up anonymously on the machines of two Western news agencies alleging that because of "lost confidence in the Poles, the Soviet committee's letter had presented an ultimatum hinting a deployment of neighboring armed forces for the protection of lines of communication" to Soviet forces in Poland and in East Germany.
Until the weekend, the situation here had been relatively calm, at least by the standards that have prevailed in Poland since last summer.
This now has changed radically. The Soviets may not have named names in their letter. But in criticizing the leadership of both the party and the government for allegedly breaking pledges about firm action against the "antisocialist forces," they are holding party chief Kania and General Jaruzelski primarily responsible.
That became clear when, for the first time in this crisis, the Russians made a direct, formal committee-to- committee approach instead of the earlier personal contacts between leaders on both sides. In Communist Party practice that is the same as saying they saw no point in holding further discussions with Mr. Kania and his Politburo colleagues.
If the Soviets are, in fact, looking for top personnel changes, the members of the Central Committee are as divided between reformers (the minority) and conservatives as are the 11 full and five alternate members of the Politburo. In any crisis probably as many as one-third would vote with the stronger wind.
But the problem, for the Russians (as well as many Poles who sense an absence of firm leadership in the present team) is who to put in Mr. Kania's place. The Politburo's lack of men of real leading caliber has been evident enough.
Thus far, the Russians had seemed to favor Stefan Olszowski. Able, moderate, and a halfway reformer, he seemed ideologically orthodox enough to satisfy them. But last week he, like many others, condemned the hard-line Katowice Forum (which Moscow approves) as an obstacle to restoring unity to the Polish party.
Poles suggest that the recent passing of the Polish primate, Stefan Cardinal Wyszynski, might be one factor behind this latest Russian move. As one sound observer remarked to this writer:
"The recent crop of anti- Soviet incidents -- the desecration of Soviet war memorials and graves, which could be hard-line provocations, or the release of confederation activists -- might have provided the last pretext. But, just as we Poles -- and party members, too -- saw Cardinal Wyszynski as the real leader of the nation, the Russians also, I believe, recognized him in that sense. . . . It creates an anxious vacuum for them as well as for Poland, particularly when even to us our own leadership seems so indecisive."
Meanwhile, 23 prominent Polish intellectuals warned of the dangers of any reversal of the reform process. Their statement reflects the tremendous domestic pressures the regime faces at the same time that Moscow is insisting that the reform process is brought to a halt.