Solidarity Tries to Define Role in Uneasy Era : Poland: Walesa and the union are slipping in opinion polls as the government runs an austerity program.

The Solidarity trade union opened its first congress in nine years here Thursday faced with the task of redefining its role in Polish society and shoring up the popularity of both the trade union and its restless leader, Lech Walesa.

With both the union and Walesa slipping in recent public opinion polls, they must decide how closely they want to identify with and support the programs of a Solidarity-led government that has launched a strict austerity program, causing factory bankruptcies and growing unemployment.

An array of government officials, including the leader of the government, Prime Minister Tadeusz Mazowiecki, were present at the opening, which provided one of several sharp contrasts between this and Solidarity’s first congress nine years ago, when the union represented a rebellion against the Communist authorities then in power.

Mazowiecki, recognizing the pressures within the union, cautioned the delegates Thursday against “the temptation to populism and demagoguery,” and asked for the union’s support for the government’s “difficult choices.”

“Our economic program is difficult,” Mazowiecki said, “but it is a great chance for Poland, a chance to see that our labor will not be wasted any more.”

Mazowiecki told the delegates, who met in the same hall where they held their first congress in 1981, that the government is developing programs of social support to cope with unemployment, which stood at 267,000 at the end of March.

Answering a recent criticism from Walesa, whose differences with the prime minister have become more evident recently, Mazowiecki said the government is working steadily to “reform state structures.” Walesa has charged that the government should move faster to replace officials of the former Communist regime in the government bureaucracies and state enterprises.

Although he was Walesa’s personal choice for prime minister, Mazowiecki has had to show a certain forebearance for Walesa’s recent sniping. As the most powerful political voice in the country, Walesa has not hidden his frustration at not having an official position from which to exercise his power. His closest allies acknowledge that he is aiming for the Polish presidency, now in the hands of the former Communist leader, Gen. Wojciech Jaruzelski.

Mazowiecki, an intellectual author of scholarly essays who won his Solidarity credentials from the earliest days of the union and has slept side-by-side with striking workers barricaded inside the Gdansk shipyards, reminded the Solidarity delegates of his political heritage.

“I am one of you, and I remain one of you,” he said. “This is the only way to explain my role. The experience I have gained among you is the greatest public experience in my life and I want to remain faithful to it.”

The union’s public approval rating has fallen from 78% in November to 47% in March, according to polls here. Walesa’s own ratings dropped from 90% to 56% in the same period.

Both the union and Walesa have suffered from related but different problems. Both are responsible for the political transformation of Poland, and both are pledged to support the results of the transformation.

For the union, this support meant a pledge of labor peace, only rarely broken, and a willingness to suffer layoffs and factory closings so that the government’s tough sink-or-swim policy toward state-owned enterprises can take effect. In this context, there is little a traditional labor union can do to defend the jobs and wages of its members.

A related threat of political irrelevance appears to haunt Walesa, who on April 10 acknowledged the assertion of his aides that he was preparing to seek the presidency of Poland. A day later, however, he claimed he was misunderstood. His more recent comments on the question appear calculated to obscure his goals, but few citizens of Poland have any doubts that he has set his sights on the office.

Walesa, in a newspaper interview, said his goal for Solidarity is “turning it into a trade union,” and creating more distance between the union and the government.