LAS VEGAS, June 12 — The United Automobile Workers' convention opened here Monday with leaders and members in a familiar fighting mood, but with a new battle plan aimed at protecting what they have rather than gaining new ground.
The change reflected the falling fortunes of Detroit's automakers, a new reality that the union's president, Ron Gettelfinger, laid out for members both in his speech and in a written report that the U.A.W. issued on Sunday.
"This isn't a cyclical downturn," Mr. Gettelfinger told the convention. "The kind of challenges we face aren't the kind that can be ridden out. They're structural challenges, and they require new and farsighted solutions."
That statement, part of an hourlong speech, drew silence from the audience.
What brought the delegates to their feet was Mr. Gettelfinger's dismissal of comments by pundits who try to argue that the U.A.W. has lost its influence.
"They think we've run out of gas intellectually and emotionally, that we've lost our will, our creativity and our nerve," said Mr. Gettelfinger, who is expected to win re-election to a second four-year term later this week.
"We've got news for them," he went on, pounding the lectern. "We're not going to surrender. We're not going to lower our sights, give up our dreams or give up our fight for a better world for our children and grandchildren."
In the short term, though, many union members at the convention said the most urgent fight was to protect the current lot of the members, to draw a line in the sand.
A Ford worker, Gary Walkowicz, said he could not support any further concessions by the U.A.W., despite Ford's financial problems.
"If we start giving concessions, the companies will only want more," said Mr. Walkowicz, who works at Ford's truck plant in Dearborn, Mich.
He was among a small group of workers who passed out bright yellow leaflets to convention delegates Monday, urging them to fight further concessions.
The leaflets, titled "Draw the Line at Delphi," asked union officials to allow open debate at the convention over resisting givebacks. "These are life and death issues for our union," said the leaflet, which was signed by more than 30 local union officials and other delegates.
Delphi, a former G.M. division that is now a stand-alone parts supplier, is operating under bankruptcy protection and seeking steep concessions from workers to lower its operating costs.
Mr. Gettelfinger has shown a willingness to negotiate when the circumstances demand it. In his speech, he gravely took responsibility for a landmark agreement, reached last year with General Motors and Ford, that required workers to pay more for health care coverage.
The deal, meant to alleviate an enormous burden that the automakers face in providing retiree health care, was "the most painful decision" he had made as union president.
Further, Mr. Gettelfinger told delegates, broader economic pressures had forced all labor groups to reset their expectations.
"In the not-too-distant past," he said, "when the U.S. economy grew and productivity increased, we could expect wages to rise as well. That's no longer true."
Mr. Gettelfinger vowed to fight for changes in bankruptcy laws, aiming his criticism at Delphi and other bankrupt parts suppliers that have demanded steep concessions from workers.
"These reforms are needed to stop unscrupulous employers and their battery of bankruptcy vultures," he said.
His voice barely audible over the delegates' cheers, Mr. Gettelfinger added, "We need to stop dead in their tracks those who would seek to void contracts with their workers while lining their pockets with everything of value and uncaringly destroying lives, hopes, dreams and communities in the process."
The mood of defiance extended to several workers interviewed near Detroit.
Tom Dean, a forklift driver with 29 years' experience at G.M.'s truck assembly plant in Pontiac, Mich., said Monday that he did not intend to accept a buyout under the programs that had been offered to workers at G.M. and Delphi.
He said he hoped his job would remain secure until he was ready to leave in a few years. As for concessions, Mr. Dean said, "We want the company to prosper, but we don't want to be taken advantage of."
Some 113,000 workers at G.M. and 23,000 at Delphi have until June 23 to decide whether to stay or go and a week more in which to change their minds.
Barbara Farrell Brown, a convention delegate who has spent 22 years at G.M.'s plant at Lake Orion, Mich., said she had already rejected a $140,000 buyout that would have allowed her to keep her pension but required that she give up retirement health care coverage.
"I'm not taking a buyout. I would not cut my ties," said Ms. Brown, who was accompanied to Las Vegas by her daughter, Stephanie, 21, a U.A.W. member at a G.M. parts supplier.
Ms. Brown said she was concerned that a number of her factory's younger workers were planning to accept the deals and leave. She said she hoped to persuade them to stay and help carry on the U.A.W.'s fight.
"A lot of our young seniority workers need to be taught how to stick together," Ms. Brown added.
The call for creative new solutions to revive the union's fortunes in a struggling industry was made by others at the convention, as well.
"We can help the auto industry win again," Senator Barack Obama, Democrat of Illinois, told the delegates via satellite. "We need to start thinking big again.
"I need for all of you to fight for the future," Senator Obama continued. "I need all of you to be open to creative ways of doing business. None of us can afford to watch the American auto industry fail. If we've got the courage to succeed, labor will rise again."
Labor experts viewed the sobering notes of the convention as a sign that the U.A.W. was facing the reality that has resulted in a drop in its membership to the lowest level since 1942. Mr. Gettelfinger noted Monday that the U.A.W. had lost more than 78,000 members in the four years since its last convention, although it managed to add 66,000 new members through organizing drives and affiliations with other unions.
For all its troubles, the union remains a force with significant power to affect the future of the auto industry, said Harry Katz, director of the Institute of Collective Bargaining at Cornell University's School of Industrial and Labor Relations.
"They're still the U.A.W.," he said.