In 1961, Martin Luther King Jr. spoke to the United Auto Workers about what the civil rights movement had learned from the labor movement. He said that, in the 1930s, “you creatively stood up for your rights by sitting down at your machines, just as our courageous students are sitting down at lunch counters across the South.”

When King was describing the “kinship” between the two movements, organized labor was strong, representing about a third of the non-agricultural private-sector workforce. The civil rights movement was still a fledgling campaign, not yet having won passage of the Civil Rights Act or the Voting Rights Act.

This Labor Day, the roles have reversed. The civil rights movement is the nation’s iconic cause. The gay rights movement, hardly a blip on the radar screen a half-century ago, is winning meaningful victories in the courts and in legislatures. But unions are on the road to virtual extinction.

Even public-sector unions, now a majority of the labor movement, are on the defensive. A new movie, “Won’t Back Down,” unfairly paints teachers unions as impediments to quality education for students of color. One character asks, “When did Norma Rae get to be the bad guy?”

To revive itself, labor must rediscover its roots as an early civil rights movement for workers. In some places, this is already starting to happen. On Aug. 11, the AFL-CIO held a massive rally in Philadelphia demanding a “Second Bill of Rights,” including the right to organize and bargain collectively. This summer, the UAW has been trying to organize a Nissanplant in Canton, Miss., where 70 percent of the workforce is African American, using a civil rights frame.

“The civil rights experience was fought on that very ground,” the UAW’s Gary Casteel told Reuters. “We’ve been saying that worker rights is the civil rights battle of the 21st century.”

In particular, unions should emulate three strategies of the civil rights movement.

First, labor must make clear, in word and deed, that it is part of a broader movement for social justice and against concentrated wealth and power, not just a special interest concerned only with its membership. The civil rights movement has succeeded when it has made a pitch for ending discrimination universally, and it has struggled when focusing on narrow, race-specific preferences. Labor has a good case to make: When union wages increase, nonunion employers respond by raising pay, too, to attract workers. And each percentage-point decline in the U.S. unionization rate has been accompanied by a comparable fall in the proportion of income going to the middle class.

Second, unions need to show that they are a vehicle for vindicating the individual rights that Americans hold dear against the power of large employers and the government. Just as King fought for individual civil rights as a fulfillment of the Declaration of Independence’s promise of equal opportunity, so the labor movement should fight for individuals’ First Amendment right to engage in the freedom of association, including the right to form a union.

Third, like the civil rights movement, labor needs to codify its notion of rights through strong federal legislation. The crowning glory of the civil rights movement is the Civil Rights Act of 1964, which through the force of law and sanctions helped delegitimize racial bias. Organized labor has the National Labor Relations Act of 1935, which institutionalizes the right to organize, but its sanctions are so weak that employers routinely flout the law and pay the penalties. In part because employers frequently fire or demote employees for trying to unionize, the watchdog group Freedom House rates the United States as less free for labor than 41 other nations.

The Civil Rights Act should be amended to outlaw employment discrimination not only on the basis of race and sex, but also for exercising the right to join a union. Doing so would allow employees to sue in federal court and to receive compensatory and punitive damages from employers. It would stigmatize employers who broke the law as civil rights violators. Without employers trying to block organization, polls suggest that many American workers would join unions, if given a free choice.

Organized labor has been written off before. But if a civil rights approach succeeds in strengthening the movement, more people will join it. And if part of the reason the gay rights movement is succeeding is that more people know someone who is gay, the growth of the labor movement could generate a similar virtuous cycle for American unions.

Richard D. Kahlenberg is a senior fellow at the Century Foundation. Moshe Z. Marvit is an employment discrimination and labor lawyer. They are the co-authors of “Why Labor Organizing Should Be a Civil Right: Rebuilding a Middle-Class Democracy by Enhancing Worker Voice.”

Read more from Outlook:

Five myths about the labor movement

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