The Soviet Union has at last decided to invade Poland, and to do it soon, because the spirit of reform has spread from Solidarity workers to the ranks of the Polish Communist Party itself.
So predicts a leading US expert in Soviet and Polish affairs, Seweryn Bialer, professor of political science at Columbia University in New York, himself part Polish and a man in touch with sources close to the Polish Politburo and sources in Moscow as well.
The professor says Moscow's strategy to enforce obedience on the 35 million Poles is to use an occupation army of at least 400,000 men and to threaten workers who refuse to work with starvation.
Later, with Soviet-style political control reimposed, Moscow will allow Poland some partial economic reforms similar to the ones now operating in Hungary, he says.
Soviet President Leonid Brezhnev went to Prague to tell other Warsaw Pact leaders of the invasion plan -- and to consult with the Kremlin's man on the Polish Politburo, Stefan Olszowski, Poland's chief representative at the Czech party congress.
Professor Bialer, a survivor of the Auschwitz concentration camp, is the author of a new book on the Soviet leadership. He is also the successor to Zbigniew Brzezinski at Columbia as director of the Research Institute on International Change.
Professor Bialer's predictions are not shared by other Soviet experts in the United States. They believe Moscow will stay out of Poland for the very reasons that have kept it from invading so far.
Those reasons include: a likely end [temporarily at least] to Western diplomatic and trade links with Moscow; an end to arms-control talks; closer ties between the US and its NATO allies in Europe; higher defense spending in NATO; a return to the cold war atmosphere of the late 1940s. (Western military action is excluded to avoid the risk of nuclear war.)
Professor Bialer shared their noninvasion views until last week. Now, supported by some other nongovernment experts, he sees the way Polish party Central Committee members behaved recently as leaving Mr. Brezhnev virtually no choice.
"One-third of the Polish Communist Party, which has about 1.7 million members , are also members of Solidarity," he said in an interview in New York. "The Central Committee of the party has now voted to approve the use of secret balloting to select delegates to the next meeting of the party congress, set for July.
"Brezhnev can't allow that. What you have now is the situation of six months ago -- worker reforms threatening party control -- plus a Dubcek situation like the one in Czechoslovakia in the first half of 1968 -- the communist leadership out of step with Moscow."
Until now, the Kremlin had hoped that the Polish Communist Party would be able to stay united and to stop or even reverse Solidarity's various demands.
But the pro-Moscow Mr. Olszowski and fellow Politburo member Tadeusz Grabski had been outvoted by moderates, including party leader Stanislaw Kania, on the decision to avert the threatened national strike by yielding some ground to Solidarity.
Professor Bialer and others see the scenario from now on like this: In the near future Moscow will choose an incident and order into violent action against workers some or all of Poland's 60,000 militarized militia (security police). Moscow will then pause, to assess reactions in Solidarity and in the West.
They believe that Poles -- brave, christian, devoted to the independence of their country -- will fight back, using caches of buried arms now in place. The degree of their opposition depends on the Roman Catholic Church in Poland.
"The church may well advise people not to fight because it wants to preserve young people for the future," the professor says. "If the church does say, 'Don't fight,' many Poles won't. But others will. It will be bloody."
The Soviet forces will win: A nation of 35 million cannot withstand a nation of 265 million for long.
Polish workers will then mount a massive campaign of passive resistance, refusing to operate machines or factories. The Soviet answer: Troops will deliver minimal, close-to-starvation food rations and warn that any Pole who refuses to work will not eat at all.
After two weeks or so, workers will sullenly begin to work, mindful of their wives, children, and relatives.
"The Soviets used 300,000 troops to occupy Czechoslovakia in 1968," the professor says. "The Czechs didn't resist. Now they'll need 350,000 to 400,000 troops to subjugate Poland at least."
Later, having blocked the road to political reforms, Moscow will permit some economic reforms. These will be along the lines Mr. Olszowski has been advocating: purely economic rather than political. They could include the kind of decentralization, aid to private farmers, and use of the profit motive that Hungary is using today.
"Janos Kadar [Hungarian party chief] is allowed considerable economic freedom because the Soviets know he is in charge and he is politically orthodox."
Can the Soviet strategy work? "The Poles have been subjugated before," the professor replies tersely. "The Germans did it in World War II, with an army of occuption. Poland as an entity was earlier wiped out for more than an century. Poles know they happen to occupy an unfortunate geopolitical location."
The professor sighs and concedes he may be wrong. But he has been right up to now.