Just this past weekend, United Airlines canceled at least 270 flights at Chicago's O'Hare International Airport, and put the blame on its pilots, who have refused to work overtime since their contract expired in April. And while the pilots' union and United continued negotiating a contract with a federal mediator, passengers were seen on television bad-mouthing pilots for selfishly trying to bolster their own six-figure salaries without concern for thousands of stranded customers.

United pilot Herb Hunter, a spokesman for the pilots' union, said he has sensed increased consumer disgust. Hunter was delayed heading toward Chicago on Saturday and walked back to the cabin to show passengers weather maps so they understood the wait had nothing to do with labor problems. "It's unfortunate that some people in management have been saying it's the labor dispute, and that is just flat not true," Hunter told the Associated Press, adding that some United pilots have refused to work overtime, but that there's no organized effort by the union.

Still, the perception exists that, collectively, pilots are choosing to harm customers.

"The one thing unions can't do is alienate the public," Kimeldorf says. "I think public support is critical in every case, because politicians care about that, and they're the ones who eventually intervene in strikes. Not having public support also can compromise a union's ability to stay together as a unit."

Workers at the United Parcel Service seemed to understand this during their two-week strike in 1997, in which the company ended up adding 10,000 full-time jobs for part-time workers. The UPS labor victory was crucial because it was the first time in many years that organized labor was able to win public support for a major strike. Using extensive advertising and public relations, the Teamsters were able to portray union workers as victims, trying to earn decent pay with part-time positions. The union also effectively painted the ranks of UPS' part-time employees as diverse, working-class Americans, and despite a disruption of service, customers seemed to forget that they weren't getting their packages -- or at least didn't mind switching to another courier. "The union got out the message that workers were making under $25,000 and that there were lots of single mothers on the picket lines," Kimeldorf says.

Says Stepan-Norris: "There's no consistency in public support for strikes. Winning over the public is something labor unions have to earn. But that's hard to do when the public is directly affected."

Employees at Verizon have raised concerns that longtime telephone workers could be pushed out if the company hires lower-paid, nonunion employees at its fast-growing wireless division. "All we want is a few crumbs from the table and don't give our jobs away," John Lang, a 32-year veteran of Verizon, told the Associated Press.

But the public, so far, does not appear moved.

"Verizon, as far as I know, offers one of the best benefit packages in the corporate world. (Free benefits.) They also have excellent working conditions ... So why are these issues on the table? I'm in total agreement with unionizing the Verizon wireless sector and seeking job protection. But come on folks, stick to the issues [at] hand," wrote one visitor to the Verizon stock message board at Ragingbull.com.

On its Web site, the AFL-CIO says negativity toward unions has waned in recent years. In 1993, one out of three Americans felt negatively toward unions, compared to one in four last year, according to a study by Peter Hart Research, commissioned by the AFL-CIO. And union membership rose from 16.21 million to 16.48 million last year, according to the federal Bureau of Labor Standards -- but that still pales in comparison to years past. In 1979, for instance, 21 million Americans were members of unions.

Now, union leaders are scrambling to boost their rolls, targeting women, minorities, high-tech workers and even college students, in an effort to keep the union spirit alive. To do this, the AFL-CIO now finds itself doing a lot of community outreach to explain what unions do, and why it's important to support them.

"Making the public aware is an important piece of leverage," says Elaine Bernard, director of Harvard University's trade union program, an executive program for union leaders. "Unions have to show that they provide a long-term benefit that outweighs any inconvenience the public may feel. But it's a challenge, because the public is a tough taskmaster."