Union membership in the private sector fell to 6.1%, a historic low.

The Economist predicts “2022 will be the year of the worker.” Interest in organizing is “infectiously spreading from workplace to workplace,” the New Republic claims, concluding: “America is in the midst of a dramatic labor resurgence.” New data from the Bureau of Labor Statistics throw cold water on these predictions.

The annual BLS report on union membership released last week shows that unions lost nearly a quarter-million members in 2021, with private-sector membership dropping to a historic low of 6.1%. Even in retail and healthcare, which labor organizers targeted over pandemic-related safety concerns, union membership declined in 2021 from 2020.

Unions have interpreted these data as evidence of an unfair marketplace rather than their own faults. “The path to formal union recognition and bargaining in this country is torture,” Larry Cohen, a former president of the Communications Workers of America, complained. His alternative, known as card check, would eliminate workers’ right to a secret ballot vote on representation. Heidi Shierholz, president of the union-funded Economic Policy Institute, argued that the “substantial level of union activity in 2021 and the polling data on union favorability” demonstrate the enduring appeal of unions.

But thinking well of unions and wanting to pay dues to be represented by one aren’t the same. I recently moderated focus groups of workers 18 to 29 in the Midwest and on the East and West coasts. While most said positive things about unions, only a handful wanted to join one. The election losses at companies such as Amazon, Nissan and Volkswagen—which unions expected to win—reflect this ambivalence. Unions lost about half of all National Labor Relations Board-supervised elections in 2021.

The “historic” worker strife that has drawn media attention is more fiction than fact. Don’t take my word for it: The socialist magazine Jacobin reviewed the new BLS data on work stoppages and concluded that 2021 “was a quiet year, even by recent standards.”

The magazine continued, with evident disappointment: “There were about half as many major strikes in 2021 as there were in 2018 (the year of the teachers’ strikes) and 2019 (which included a five-week strike against GM), and nothing compared to the pre-Reagan decades.”

There is some good news for organized labor. In recent months, Workers United, an affiliate of the Service Employees International Union, organized two Starbucks locations in Buffalo, N.Y., and filed for elections in roughly two dozen other stores nationwide. The union’s strategy was bolstered by a controversial NLRB decision allowing the union to organize and bargain separately by store rather than city or region. Organizers can cherry-pick store locations where employees are inclined toward union representation.

But there is a good reason few other unions have pursued this strategy. Starbucks operates about 9,000 stores in the U.S. The union will likely need to organize hundreds of locations before Starbucks management considers a companywide agreement. Meanwhile, many baristas may realize, as millions of Americans before them did, that with a union, you don’t always get what you bargain for.

Mr. Saltsman is managing director of the Employment Policies Institute.