Passive resistance - not violence - is likely to be the most effective course for Polish workers over the long run, according to American experts on the subject.
Reagan administration officials and a number of nongovernment experts seem to agree that violence could lead to civil war and a Soviet invasion of Poland. An invasion is the last thing most Washington officials would like to see.
But passive resistance such as a work slowdown, the signs of which are now apparent in some parts of Poland, would be difficult to suppress, the experts say. It involves less risk on the part of the participants. It is difficult for the authorities to assign the blame for it. And because of the economic consequences which it could bring, it might force the Polish authorities to reach an accommodation with the Roman Catholic Church and with the trade union movement.
For the moment, the most articulate advocate of passive resistance outside the US government seems to be Zbigniew Brzezinski, former national security adviser under President Carter. As Mr. Brzezinski explained it in a breakfast meeting with reporters, unless there is passive resistance, the Solidarity trade union movement will be crushed.
But in order for passive resistance to be sustained, according to Brzezinski and several other experts, there must be a constant flow of information to the Polish workers about what is happening inside Poland and in the West. If the workers feel that they are isolated and that the West is indifferent to their plight, then resistance will fade, says Brzezinski, a scholar of Polish origin who is now with the Georgetown University Center for Strategic and International Studies.
Brzezinski's view is shared by a number of officials in the Reagan administration. They have to be more cautious than he is in what they say. But a senior State Department official said several days ago all was not lost in Poland, partly because of the Polish workers' ability to engage in work slowdowns - essentially, to go to work but not do anything.
Reagan administration officials recognize that getting information to Poland is important. The Voice of America (VOA), the US government-funded international radio, has increased its broadcasts to Poland from two and a half to more than five hours a day. President Reagan's statement on Poland, planned for the evening of Dec. 23, was to be broadcast live to Poland as well as to other nations.
Travelers from Poland have reported that VOA broadcasts, as well as those of the British Broadcasting Corporation (BBC) have been coming through clearly in Poland. But Radio Free Europe (RFE), the Munich-based radio funded by the US Congress, has been constantly and heavily jammed by Polish and Soviet authorities. RFE has the advantage of round-the-clock service, and retransmits news that it picks up from Polish shortwave radio broadcasts.
''Passive resistance depends on . . . signs of support,'' says Stanislaw Wasowski of the Georgetown School of Foreign Service, a onetime member of the Polish underground who fought against the Nazis. ''It is a psychological thing. Those who are resisting must feel that they are not alone, and that they are resisting for a purpose.''
Mr. Wasowski says that when he was a prisoner of the Nazis in the winter of 1945 working on a railroad line in southern Austria, he and other workers became experts at passive resistance. While two workers in a four-man work team loaded coal onto railroad cars, the other two put sand in the locomotive's axles, he said. They also stole whatever they could.
Meanwhile, former Secretary of State Henry A. Kissinger suggested Dec. 22 on a WETA television program sponsored by Georgetown University that the US consider recalling its negotiators from two conferences with the Soviets - the talks concerning implementation of the Helsinki accords and the Geneva talks on nuclear weapons - in reaction to ''Soviet-inspired repression.''